Foliage Type Research Articles

Defoliadores de roble (Nothofagus obliqua), raulí (N. alpina), coigüe (N. dombeyi) y lenga (N. pumilio)

Defoliator species always has been associated to Chilean native forests, but never developing into a serious pest. Now probably due to human intervention in forest and some climatic changes, some population dynamics of defoliator insects has been changed, affecting the forests health. Nevertheless as all are native species have biocontrollers, mostly parasitoids. Through bibliographical research, a list of the main defoliators insects that attack Nothofagus obliqua, Nothofagus alpina, Nothofagus dombeyi and Nothofagus pumilio was made. The following data was reviewed: associated species, type and magnitude of damage and the stage of the insect that produced the main damage. To evaluate the magnitude of the damage, some factors such as economic importance of the tree species, its significance within the native forests and type of foliage (deciduous or perennial) were considered. The results show that Nothofagus obliqua and Nothofagus dombeyi have the main number of associated defoliators. Hornius grandis is the most poliphagous species, found in Nothofagus obliqua, N. alpina and N. dombeyi. Among the types of defoliators, masticators are predominant. The most frequent species associated to the four tree species that were studied are: Hornius grandis Philippi and Philippi, Cerospastus volupis Konow, and Ormiscodes cinnamomea Feisthamel.

The anatomy and seed plant affinities ofRhacopterisandSpathulopterisfoliage from the Dinantian (Lower Carboniferous) of Scotland

AbstractPermineralised material ofRhacopteris lindseaeformis(Bunbury) Kidston andSpathulopteris obovata(Lindley & Hutton) Kidston, showing both external morphology and excellent anatomical preservation, is described from the Lower Carboniferous (?Asbian, Upper Viséan) tuffs and dolomitic ashes outcropping at Weaklaw–Gullane, East Lothian, Scotland. These specimens provide the first anatomical information on these two well-known plant compression genera. The rachises haveLyginorachis-type anatomy with distinctive characters in the two species.Spathulopterisrachises correspond toLyginorachis kingswoodenseMeyer-Berthaud, previously described from the localities of Kingswood and East Kirkton, whereasRhacopterisshows similarities with the petiole attributed toBiligneafrom Oxroad Bay. Both foliage types conform to seed-fern frond organisation. This new evidence contradicts previous interpretations ofRhacopterisas a fern or a progymnosperm. We suggest thatRhacopteris lindseaeformisandSpathulopteris obovatarepresent the foliage of some of the arborescent gymnosperms which are found associated in several contemporaneous localities.

Variability of Seed and Plant Development in Pea

Pea (Pisum sativum L.) yields are generally highly dependent on seed number. The objective of the present study was to investigate seed and plant development of 10 contrasting genotypes of pea with differences in seed size (0.1–0.3 g seed−1), foliage type (semi‐leafless and leafed), and number of branches. The periods of seed set and seed filling were studied in the field for 2 yr at two sowing dates. Seed water content (WC) was closely related to seed development. Seed water content at beginning of seed filling and at physiological maturity corresponded to 0.85 and 0.55 g g−1 fresh weight, respectively. The progression of flowering, beginning of seed filling, and physiological maturity along the stem were linearly related to cumulative degree days from the beginning of flowering. The rates of progression of flowering and of beginning of seed filling were not dependent on environmental conditions, but they were significantly different among genotypes. Conversely, the duration of the lag phase, time between flowering and beginning of seed filling at the first node, remained stable in spite of differences in seed size. The onset of physiological maturity was more variable. Duration of seed filling varied among environments, but genotypes had similar durations in spite of differences in seed size. Seed number on the main stem was fixed when the seeds of the last reproductive node began to fill. The delimitation of the seed set period showed genetic variability for the beginning of the period, depending on the first reproductive node number, and its duration.

Initial deposits and persistence of azadirachtin in fir and oak foliage after spray application of ‘Margosan‐O’® formulation

AbstractFoliar deposits and persistence of azadirachtin were investigated after spraying ‘Margosan‐O’® formulation at three dosage and volume rates on to balsam fir and oak seedlings in a laboratory chamber. Droplet‐size spectra and deposits were assessed using artificial samplers, and foliar residues were measured by high‐performance liquid chromatography (HPLC) at different intervals of time after treatment. Disappearance of azadirachtin from both types of foliage was rapid, and the DT50 (the time required for 50% of the initial concentration to disappear) values ranged from 17 to 22 h. The initial azadirachtin concentrations varied widely from 4 to 96 μg g−1 (fresh weight), but the rate constants 0.0311 to 0.0414, were not significantly different. The data thus indicated a poor relationship between initial concentrations and the rate of loss.The influence of spray droplet size and cuticular wax content of foliage on persistence of azadirachtin was investigated using both foliar types, and glass microscope slides without and with the foliar wax coating. Neither the type of surface nor the droplet size influenced the persistence. The rate of azadirachtin loss from the glass slides was faster than from both types of foliage, and was unaffected by the presence of wax coating. The fir foliage had higher cuticular wax content than the oak foliage, but the persistance of azadirachtin was similar in both foliar types.

Fruittree Leafroller, Archips argyrospila (Walker) (Lepidoptera: Tortricidae), Performance as Influenced by Host Foliage Type

Performance of early and late instars of the fruittree leafroller, Archips argyrospila (Walker), was quantified from bioassays using previously uninfested foliage of baldcypress (Taxodium distichum L.) and two other potential hosts. Initial survival and host preference tests indicated that open morphology baldcypress foliage was more suitable for first instars than either appressed morphology baldcypress or pondcypress. Growth, development, and host utilization indices, based on rearing of late instars, revealed that open morphology baldcypress foliage was most susceptible to defoliation. Late-instar bioassays also indicated that pondcypress foliage was the least susceptible cypress foliage type tested, due to mechanism(s) triggering early termination of larval development. The appressed morphology baldcypress foliage was of moderate susceptibility, apparently because of foliage characteristics deterring its consumption. Shumard oak, Quercus shumardii Buckl., and sweet citrus, Citrus siniensis (L.), did not support early-instar survival or late-instar development and, thus, appear to preclude the threat of fruittree leafroller defoliation in the Gulf States. The results indicated that there is a high potential for fruittree leafrollers to infest areas where pondcypress occurs.

Rates of apparent photosynthesis, respiration and dry matter accumulation in maize canopies

The rates of canopy apparent photosynthesis (PC) and canopy respiration (Rc) were studied during vegetation season in two erectophile and two planophile hybrids of maize (Zea mays L.) grown at two canopy densities [7.5 plants m-2 (HD) and 4.5 plants m-2 (LD)]. Large differences in PC, Rc, RC/PC, leaf area index (LAI), dry matter accumulation and grain yield were found among hybrids and plant densities. Variations in PC and RC were associated mainly with changes in LAI. There was also found change in PC per unit LAI with time. The average RC/PC was 28.9 % for all treatments throughout the vegetation season. PC and RC per unit dry matter were higher in LD than in HD and decreased throughout the measurement period. The HD stand had higher PC and yield in hybrids with erectophile foliage, whereas LD stand had higher PC after male tetrad and got higher yield in hybrids with planophile foliage. Only RC in hybrids of the two foliage types was higher under HD than under LD throughout the vegetation period.

Soybean Genotype Effects on Bigeyed Bug Feeding on Corn Earworm in the Laboratory

Corn earworm, Helicoverpa zea (Boddie), is a serious pest of many crops, including soybean, Glycine max (L.) Merr. This study was conducted to determine whether or not plant pubescence could be used to enhance predator activity. The influence of plant pubescence or insect resistance of soybean on predation of corn earworm eggs by the bigeyed bug, Geocoris punctipes (Say), was investigated in the laboratory. Bigeyed bug adults were allowed to feed on corn earworm eggs that were placed on foliage of soybean genotypes isogenic for dense, normal, or no pubescence, and on genotypes susceptible or resistant to foliar feeding insects. Percent egg puncture by males was similar on all foliage types whether or not choices were offered. Females punctured significantly (P < 0.05) more eggs on normal leaflets in a no choice situation. Significant differences (P > 0.05) were not detected in percent egg puncture on soybean genotypes resistant to foliar feeding insects as compared with susceptible genotypes (‘Centennial’ and ‘Davis’). Development of soybean cultivars with reduced pubescence, which is less preferred by corn earworm for oviposition and/or foliar feeding, will probably not influence this beneficial predator, since egg predation was not adversely affected by plant pubescence or insect resistance under laboratory test conditions.

Role of Tree Trunks, Foliage Type, and Canopy Size in Host Selection by Lymantria dispar (Lepidoptera: Lymantriidae)

In caged choice experiments, Lymantria dispar (L.) larvae strongly preferred Acer saccharum Marsh. and Fraxinus pennsylvanica Marsh. trunks (44.3 and 43.3% of larvae, respectively) to Betula papyrifera Marsh. trunks (5.7%). When larvae were allowed to choose among the foliage of live seedlings of the same species, they preferred B. papyrifera (71.0%) over A. saccharum (14.3%) and F. pennsylvanica (0.7%). Trunk sections of A. saccharum and B. papyrifera were wrapped around live seedlings of the same trees and F. pennsylvanica in six possible combinations of trunk and foliage species to evaluate the impact of trunk characteristics on host selection in the presence of foliage. The most preferred trunk-foliage combinations, in descending order of percentage larvae found on each, were as follows: A. saccharum-B. papyrifera (41.0%), B. papyrifera-B. papyrifera (19.0%), A. saccharum-A. saccharum (14.8%), B. papyrifera-A. saccharum (12.2%), A. saccharum-F. pennsylvanica (2.2%), and B. papyrifera-F. pennsylvanica (1.0%). Both trunk species and foliage species Significantly influenced larval choice. The effect of tree canopy size, as measured by leaf surface area, on the distribution of larvae was measured in a forest clearing where five replications of 17 tree species and cultivars were planted. The tree species ranged from highly susceptible ( Malus sp.) to highly resistant ( Gleditsia triacanthos L.). The number of larvae per tree was explained well by the size of the leaf canopy for the six most preferred tree species and cultivars. This relationship did not exist for the remaining 11 species and cultivars of less preferred trees. Apparently, the size of preferred trees influences the distribution of gypsy moth larvae among them.

Seasonal Variation in Leaf Component Allocation in Normal, Afila, and Afila-tendrilled Acacia Pea Foliage Near-isolines

In pea (Pisum sativum L.) the af gene replaces leaflets with tendrils, and the tac gene restores small leaflets to the terminal portion of the tendrils of afaf plants. Normal (AfAf-TacTac), afila (afaf-TacTac), and afila-tendrilled acacia (afaf-tactac) near-isogenic lines in three genetic backgrounds were evaluated for 2 years in two locations to determine allocation of foliage area and weight of foliage components throughout the growing season. The percentage of total leaf area and weight due to stipule, tendril, leaflet, and tac leaflet were measured three times during the growing season in each environment. Highly significant foliage-type effects were detected for the percentage of leaf area and weight due to stipule and tendril at each sampling date. The pea leaf canopy exhibits large fluctuations in area and weight component allocation throughout the growing season. At 28 days after planting, stipules comprised 34%, 76%, and 53% of the total leaf area, and tendrils comprised 6%, 24%, and 13% of the total leaf area in normal, afila, and afila-tendrilled acacia types, respectively. At harvest, stipules composed 43%, 60%, and 53% of the total leaf area and tendrils composed 15%, 40%, and 22% of the total leaf area in normal, afila, and afila-tendrilled acacia types, respectively. Results from this study demonstrate that significant seasonal variation in allocations of foliage area and weight components exists among these three foliage types.

Evaluation of the Afila‐Tendriled Acacia (afaf‐tactac) Pea Foliage Type under Minimal Competition

The afila (af) and tendriled‐acacia (toe) genes condition structural modifications of the pea (Pisum sativum L.) leaf. The of gene replaces leaflets with tendrils and tac restores small leaflets to the tendrils of of plants. The agronomic performance of plants carrying tac in combination with of is unknown. Therefore, the objective of this research was to evaluate a near‐isogenic set of three foliage types: normal (AfAf‐TacTac), afila (afaf‐TocToc), and afila‐tendriled acacia (afaf‐tactac) in three genetic backgrounds. The evaluation was conducted under minimally competitive conditions on widely spaced wire trellises in order to allow for maximal foliage expression. Averaged across genetic backgrounds, tac increased the total foliage area of afaf‐tactac plants over afaf‐TacTac plants by 37%. Green pea yield did not differ significantly among the three foliage types. Dry seed yield at afaf‐tactac plants was significantly higher than afaf‐TacTac plants and equal to AfAf‐TacTac plants. Expression of the tac gene varied significantly with genetic background. The afaf‐tactac combination in the latest maturing background exhibited the largest increases in yield and yield components over its constituent foliage types.

Evaluation of the Afila‐Tendriled Acacia (afaf‐tactac) Pea Foliage Type under Minimal Competition

The afila (of) gene replaces pea (Pisum sativum L.) leaflets with tendrils, and the tendriled‐acacia (tac) gene restores small leaflets to the tendrils of af plants. The agronomic performance of plants homozygous for both af and lac has not been studied. A near‐isogenic set of three foliage types: normal (AfAf‐TacTac), semi‐leafless (afaf‐ TacTac), and afila‐tendriled acacia (afaf‐tactac) in three genetic backgrounds was evaluated for 2 yr in two locations using a normal plant population for pea grown for processing. The objective of the study was to measure performance of afaf‐tactac in comparison with afaf‐TacTac and AfAf‐TacTac at high levels of interplant competition. At the green pea harvest stage, the total foliage area of afaf‐tactac plants was 10% greater than for afaf‐TacTac, but not significantly different from AfAf‐TacTac. Yield of afaf‐tactac averaged 29% lower than AfAf‐TacTac and 26% lower than afaf‐TacTac in the early and midseason genetic backgrounds, but did not differ significantly in the late genetic background. Significant increases in vine length, number of nodes, lowest pod‐bearing node, and first node with nonsenescent foliage were measured in afaf‐tactac over AfAf‐TacTac and afaf‐TacTac in the early and midseason genetic backgrounds. The addition of leaflets to the tendrils of a/a/plants through incorporation of the tac gene did not result in green pea yield improvement of plants grown at a standard highly competitive population density.

Performance of populations derived by selecting for resistance to potato leafhopper in A 4XSolanum Tuberosum X 2XSolanum Chacoense cross

Intercross and backcross populations derived from aSolanum tuberosum L. (2n = 2x = 48) ×Solanum chacoense Bitt. (2n = 2x = 48) cross by selecting for resistance to potato leafhopper (PLH) (Empoasca fabae Harris), were tested in the field. In F2 and F4 populations, the levels of nymphal infestation and leaf necrosis from PLH feeding were considerably lower and tuber yields were much lower compared with those measured on the susceptible cultivar Kennebec. No differences were found between the two populations. Backcrosses of the F2 and F4 populations toS. tuberosum decreased resistance to PLH. Resistance to infestation was still greater than that of Kennebec; severity of leaf necrosis equaled that of Kennebec. Tuber yields increased, but were less than Kennebec’s yield. Foliage types shifted closer to those ofS. tuberosum. Three generations of selection and intercrossing within the backcross populations did not change the level of resistance to PLH but did tend to lower tuber yields. Foliage types remained primarilyS. tuberosum in appearance although distinctive types segregated with increased frequency. A second backcross toS. tuberosum did not change the level of resistance to PLH or the level of tuber yield relative to those of the first backcross or Kennebec.

Upper Cretaceous Conifer Leaf Fossils from the Black Creek Formation with an Assessment of Affinities Using Principal Components Analysis

Five types of fossil conifer foliage from the Upper Cretaceous Black Creek Formation of North Carolina have been reexamined from newly discovered material. The cuticular and gross morphology of Androvettia carolinensis, Brachyphyllum squammosum, Brachyphyllum sp., Geinitzia reichenbachii, and Moriconia cyclotoxon is described and illustrated. To determine the affinities of these nonreproductive remains, data for sixteen characters of leaf and cuticle morphology were gathered for the modern conifers and the fossil taxa and analyzed using Principal Components Analysis (PCA). Once characters were identified that caused known family members to sort into correct family groups with PCA, it was assumed that the fossil taxa scored for the same characters would cluster with family groupings, indicating affinities. This analysis indicates that A. carolinensis and Brachyphyllum sp. are members of the Hirmerellaceae and G. reichenbachii and B. squammosum are members of the Araucariaceae. The affinities of M. cyclotox...

Evolution of Acmopyle and Dacrycarpus (Podocarpaceae) foliage as inferred from macrofossils in south-eastern Australia

Macrofossil specimens of Dacrycarpus and Acmopyle from south-eastern Australia are investigated. The specimens previously assigned to D. praecupressinus are revised, with one placed in a different genus and new species, Podocarpus witherdenensis, and some placed in a new species, D. latrobensis. One specimen is retained as the lectotype of D. praecupressinus. Dacrycarpus eocenica is re-examined and it is concluded that this species is not Dacrycarpus, but probably belongs to an extinct podocarpaceous genus. Dacrycarpus setiger is transferred to Acmopyle, and three new Acmopyle species, A. florinii, A. glabra and A. tasmanica, are described. It is hypothesised that during the Tertiary in south-eastern Australia stomatal distribution was reduced on Dacrycarpus and Acmopyle foliage. In Dacrycarpus the bilaterally flattened foliage type (which has a greater photosynthetic area than the bifacially flattened foliage) became rare or extinct after the Early Oligocene, prior to the extinction of the genus in the region. Acmopyle has not been recorded in the region after the Early Oligocene. A trend towards reduction in leaf size at high latitudes has previously been demonstrated in angiosperms but not gymnosperms and, along with the reduction of stomatal distribution, probably represents convergent evolution in response to climatic change.

A lower carboniferous plant assemblage from La Serre (Montagne Noire, France). Part II. Gymnosperms

The Tournaisian plant assemblage from La Serre, Montagne Noire, France contains 21 elements which are assigned to the gymnosperms. They include stems of Calamopitys, petioles of Kalymma and small branched axes referable to Lyginorachis. Five types of foliage are identified of which two are preserved both as permineralization and compression. These are most comparable with species of “ Cyclopteris” Unger and represent some of the most common elements of the assemblage. The anatomy of this foliage is well preserved and is compared with previously described, permineralized foliage from the Montagne Noire. Six types of presumed reproductive organs are described from compression material. Four of these are suggested as having affinities with gymnosperms whilst two others are problematical. The flora from La Serre represents a different assemblage of plants from those seen elsewhere in the Montagne Noire although there are some elements which are undoubtedly common to all. This may be explained to some extent by the fact that the depositional sequence at La Serre represents a more near-shore depositional environment than outcrops of lydite found elsewhere in the Montagne Noire. The new data from La Serre confirms the floral similarities between the Montagne Noire in Southern France, the Cypridina Schiefer of Saalfeld, East Germany and the New Albany Shale in the U.S.A.

Avian foliage structure preferences for foraging and the effect of prey biomass

Aviary experiments using artificial foliage were conducted on two paruline warblers, black-throated blue warblers, Dendroica caerulescens, and black-throated green warblers, D. virens, to determine whether these bird species display foliage structure preferences when prey biomass is equal on each foliage structure, whether their preferences are consistent and transitive, and whether increasing prey biomass can reverse their preferences. Most black-throated blue warblers displayed preferences for structures simulating sugar maple, Acer saccharum, foliage at the distal region of the branch (short sugar maple) over structures simulating yellow birch, Betula alleghaniensis, foliage (artificial yellow birch) and over structures simulating sugar maple foliage on the region of the branch more proximal to the trunk (long sugar maple). The artificial yellow birch foliage was generally preferred over the long sugar maple. Most black-throated green warblers displayed no preference between short sugar maple and yellow birch, but preferred both of these over long sugar maple. In all cases, preferences were consistent and transitive, and increasing prey biomass reversed the preference. However, the increase in prey biomass needed to reverse the preferences of black-throated green warblers was greater than for black-throated blue warblers. These structure preferences may be based on considerations of the costs and benefits of foraging on the different foliage types.

Descomposicion del Follaje en Diversos Ecosistemas Sucesionales Tropicales

To evaluate the effect of foliage type on decomposition, we monitored the decay of a representative mix of autochthonous leaves in each of three vegetation types: 2-yr-old successional vegetation; an investigator-designed community that mimicked the phys- iognomy and species richness of the successional vegetation; and a young plantation of the tree, Cordia alliodora. To evaluate the effect of environmental differences among vegetation types on decomposition, we monitored the decay of a uniform substrate (leaves of C. alliodora) in those same three stands as well as in a vegetation-free plot. Foliage of the imitation of succession decayed most rapidly, losing half of its mass, N, P, K, Ca, Mg, and S in 1 to 3 weeks. Foliage of the successional vegetation decayed somewhat more slowly, losing half of its initial mass and initial contents of all elements except N and S in 2 to 6 weeks. Leaves of the tree grown in monoculture, C. alliodora, decomposed very slowly, losing only 22% of their mass, and less than 50% of all elements monitored except K and P, during the 15 weeks over which decomposition was measured. Mass loss and loss of N, Ca, and Mg (but not P, K, or S) were significantly faster in the bare plot than in vegetated plots, but differences in decay among foliage types were much greater than differences among ecosystems. Sustained nutrition of the successional mimic may depend heavily on rapid uptake of mineralized nutrients, whereas recalcitrant litter niay slow recycling in plantations of C. alliodora.

Juvenile/total foliage ratios inEucalyptus nitens and the growth of stands and individual trees

Individual trees and stands of two provenances of Eucalyptus nitens which have marked differences in retention of juvenile foliage were studied in four plantations at different elevations. The proportion of juvenile to total foliage and growth was measured at the end of the 2nd, 3rd and 4th year from establishment. Between the ages of 2 and 4 years annual stem volume increment increased in proportion to the amount of juvenile foliage retained. By age 4 years, stem volume of trees of the juvenile persistent form was significantly larger than that of the early adult form. Increasing differences in height growth with age between provenances, which were highly significant across sites by age 4, contributed to these differences in performance. There was some evidence that the largest trees of the juvenile-persistent form were those which combined mature foliage above juvenile foliage for the longest period during the transition from juvenile to mature foliage. In the early-adult form the largest trees were those which completed the transition to mature foliage rapidly. There was no difference in the ratio of foliage mass to basal area between the two forms. It is suggested that the faster growth of the juvenile-persistent form is related to higher leaf area index and not to foliage type. A provenance of E. globulus which had a higher retention of juvenile foliage at age 4 than a second provenance had a lower stem volume, thus indicating that in this species early growth rate is not determined by foliage type.

On Neuropteris brongniart and Cardiopteridium nathorst from the early carboniferous price formation, southwestern Virginia, U.S.A.

Collections of compressions and impressions of fossil plants from several outcrops of the Lower Mississippian Price Formation in southwestern Virginia have yielded numerous well preserved vegetative and reproductive structures, some of which are new and others referable to previously described taxa. Among these are two foliage types, here identified as Cardiopteridium Nathorst and Neuropteris Brongniart, which are more extensively and better preserved than any previously collected ones. They thus represent the first clearly documented occurence of these foliage types in the Lower Carboniferous of North America. Bipinnate fronds terminated by pinnules conforming in every respect to Neuropteris Brongniart are described and are referred to N. antiqua (ex Cycadopteris antiqua Stur). Comparison with the genus Neurocardiopteris Lutz is made and the suggestions of Hartung (1938) and Gothan (1949) that specimen attributed to this genus should be called Neuropteris are supported. A survey of the literature shows that possibly four species of Neuropteris, N. antiqua, N. antecedens, N. broilii and N. loshii, existed in the Early Carboniferous. The specimens referable to Cardiopteridium Nathorst consist of slender axes or portions of bipinnate fronds on which are borne orbicular or reniform pinnules attached by slender pedicles. Pinnule venation is dichotomous, with individual veins converging at the base. The specimens compare best with Cardiopteridium nanum f. spetsbergense described by Walton (1941), Gothan (1949) and Daber (1959) from Early Carboniferous localities in Europe. They are distinguished from isolated pinnules or parts of branch systems of Fryopsis (ex Cardiopteris) by aspects of frond and pinnule morphology. While the affinities of these foliage taxa remain uncertain, present knowledge suggests that Cardiopteridium, on the basis of leaf characters, more likely is the foliage of a progymnosperm or pteridosperm. Neuropteris traditionally has been regarded as foliage of some medullosan pteridosperms although confirmation of attachment is needed; if so, its undoubted presence in the Early Carboniferous constitutes the earliest record of the group.

Aspects of Permian palaeobotany and palynology. VIII. On the reclassification of the West- and central European species of the form-genus Callipteris brongniart 1849

The Late Palaeozoic form-genus Callipteris Brongniart non Bory includes some 135 species. Actuated by the controversies on the value of Callipteris as an index fossil for the Permian and by the possible significance of Callipteris for gymnosperm systematics, detailed investigations on the West- and Central European representatives of this genus have been carried out. The present paper deals with the problems on the taxonomy and nomenclature of the genus. Primary importance has been given to the recognition of natural taxa. Our improved knowledge on Callipteris has led us to the belief that, in a strictly morphological sense, the genus represents a highly heterogeneous group. Moreover, the recognition of reproductive organs assignable to two species of Callipteris enables the interpretation of these assembled plants in terms of a natural classification. Because the generic name Callipteris Brongniart is a later homonym of Callipteris Bory and arguments previously given (Kerp, 1981) for the conservation of the generic name Callipteris Brongniart are no longer valuable, Callipteris Brongniart has to be rejected (Kerp, 1986). The genus Autunia Krasser is emended to include both vegetative and reproductive organs, thus gaining a natural status. Autunia can be assigned to the family Peltaspermaceae. Taxonomic remarks on the Peltaspermaceae are given. The combinations A. conferta and A. naumannii are formally introduced. In addition a selection of valuable West- and Central European species formerly assigned to Callipteris are transferred to five different form-genera, defined to include the wide diversity of callipterid foliage types: viz., Rhachiphyllum Kerp nov. gen., Lodevia Haubold et Kerp nov. gen., Arnhardtia Haubold et Kerp. nov. gen., Sphenocallipteris Haubold et Kerp nov. gen. and Dichophyllum Elias ex Andrews. The following new combinations are formally introduced: Rhachiphyllum curretiensis, R. diabolica, R. lodevensis, R. lyratifolia, R. schenkii, R. subauriculata, Lodevia bibractensis, L. suberosa, L. nicklesii, L. oxidata, Dichophyllum flabellifera, Arnhardtia mouretti, A. scheibei, Sphenocallipteris bergeronii, S. raymondii and S. strigosa.