Minute Tubercles Research Articles

Developmental Characteristics of Eggs and Yolk Sac Larvae of Korean Striped Bitterling, Acheilognathus yamatsutae (Cyprinidae), Spawning in Mussels

This study investigated the characteristics of the eggs and yolk sac larvae of Korean striped bitterling, Acheilognathus yamatsutae, spawned and grown In mussels. The number of eggs in the ovary was small (<TEX>$358{\pm}108$</TEX> SD). The eggs were oval and large, and the formation of the perivitelline space was narrow. The eggs were hatched at only 41 hours after fertilization but the hatched larvae were underdeveloped. The development of yolk projection and minute tubercles on the skin surface was notable, along with the vividly moving tail in the hatched larvae. The yolk projection and minute tubercles were disappeared upon enhancement of the motor ability of the larvae was enhanced. The formation of eyes and body pigments of the larvae was relatively delayed in comparison with that of other cyprinid larvae. After completely consuming the yolks the larvae escaped from the mussel for free swimming and exogenous feeding.

Microsculpture and phylogenetic significance of the spermatheca of black flies (Diptera: Simuliidae)

The highly varied spermatheca of black flies provided an under-studied character system for phylogenetic reconstruction of the Simuliidae. Scanning electron microscopy of the spermatheca of 17 simuliid species elucidated folds and spicules on the inner surface; callosities, anastomosing ridges, and minute tubercles on the outer surface; and an intricately fluted spermathecal duct. The spermatheca of Parasimulium crosskeyi, the most plesiomorphic taxon, had a slightly wrinkled inner surface and an outer surface with acutely raised polygonal ridges. Species hypothesized to be among the basal lineages of the simuliids (e.g., Helodon susanae and Prosimulium magnum) had an irregularly folded inner spermathecal surface, but their relationships were not well resolved on the basis of information about the spermatheca. More evolutionarily derived species, including a number of species in the genus Simulium, had short or filiform spicules on the inner surface of the spermatheca. Although the use of a single character system, the spermatheca, did not fully resolve relationships among Simuliidae, its utility as a rich source of phylogenetic information was demonstrated.

Two New Brazilian Species of Oryctina (Loranthaceae) with a Revised Key to the Genus

Two new species from central Brazil of the South American genus Oryctina (Loranthaceae) are described and illustrated, 0. eubrachioides Kuijt and 0. quadrangularis Kuijt. The absence of a calyculus in the male flower of several Oryctina species represents a nearly unique feature within the family, and the lack of staminodia in the female flower has elsewhere been noted only in two species of Cladocolea. The affinities of Brazilian species with Venezuelan ones are briefly discussed. Distinctions between the two groups of species, based largely on the structure of bracteoles and staminodia, suggest that the generic name Maracanthus may have to be revived for the Venezuelan species. A new key to the genus is presented, including the new species. In recent years, the South American genus Oryctina (Loranthaceae) has significantly swelled from its original monotypic status (Kuijt, 1991). The genus currently consists of six species, but recent collections have brought to light two more, distinctive Brazilian species. Both are herein described and illustrated, and followed by some general comments on the genus, including a new key to all species now comprising Oryctina. Oryctina is one of 16 hemiparasitic genera of Loranthaceae, all of which are strictly limited to the New World. This group of genera may consist of two distinct lineages as indicated by flower size and other features, Oryctina being part of the smallflowered group also containing the better known and larger genera Phthirusa and Struthanthus. Nearly all New World Loranthaceae possess an inconspicuous calyculus directly below the 4 to 6(7) petals. The frequently minute flowers and, upon occasion, the much contracted inflorescences, have in the past posed considerable challenges to the taxonomic interpretation of some of these genera. Oryctina eubrachioides Kuijt, sp. nov. TYPE: Brazil. Minas Gerais: Januaria, Vale do Peruaqu, inicio do Cerrado de Judas, 15*7'10S, 44*13'21W on Aspidosperma, Salino & Gotschalg 4037 (holotype, BHCB not seen; isotype, LEA). Figures 1, 2. Frutex dioicius, squamatus, gracilis; internodiis ad 1.5 cm longis, teretibus. Folia ad 1.5 mm longa, cucullata peltata. Spicae paene sessiles, ca. 4 mm longae. Squamate plants, sparsely branched, the branches very slender, stiff, internodes to 1.5 cm long, terete, covered with innumerable raised stomata forming conspicuous, minute tubercles. Leaf-scales about 1.5 mm long, strongly cucullate and peltate, fringed with dark brown hairs, the adaxial surface also with brown hairs, hairs becoming white with age, leaf-scales paired but in threes on vigorous shoots. Dioecious, the inflorescences nearly sessile, about 4 mm long at anthesis, in the male plant often some 20 pairs in series on an unbranched shoot, mostly singly in the axil of scale-leaves, sometimes with a second, smaller, superposed inflorescence; peduncle somewhat less than 1 mm, followed by up to 10 pairs of brown-fringed, minute scale-leaves, each subtending a bright lemon-colored bud or flower, the mature bud ca. 1 mm diam., globular, flanked by 2 laterally placed, very inconspicuous, blunt, hair-fringed prophyllar bracteoles. Petals 6, strongly dimorphic in both sexes, the longer ones 1 mm long, shorter ones ca. 0.5 mm. Male flower lacking a calyculus, anthers ca. 0.25 mm, globular but slightly bilobed, bilocular, sessile on the middle of the petals; style 0.5 mm long, cylindrical, stigma not differentiated. Female flower 1.5 mm long when mature, half of which is ovary, calyculus distinct, petals without staminodial remnants, style to 0.5 mm long, cylindrical, stigma slightly differentiated as a terminal swelling, very slightly papillate. Fruit at least 3 x 1.5 mm, ellipsoid but with a somewhat expanded calycular region, blunt-tipped. The specific name indicates a striking general similarity to the genus Eubrachion (Eremolepidaceae), a similarity that is carried through to the more or less peltate scale-leaves (see the illustration in Kuijt, 1988, fig. 2d & e). In the present species, however, the scale-leaves are profusely fimbriate, which is not true for Eubrachion. The partial base of the plant included in the LEA specimen cited below suggests that no epicortical roots are present in 0. eubrachioides. The occurrence of such roots and/or their placement on the plant in NovoN 10: 391-397. 2000. This content downloaded from 157.55.39.40 on Thu, 28 Apr 2016 06:21:17 UTC All use subject to http://about.jstor.org/terms

Tuberculation in spatangoid fascioles: Delineating plausible homologies

The existing definition of spatangoid fascioles as a narrow band of minute tubercles (miliaries) is inadequate. One reason is that many intermediates between the presence of indisputable fascioles and their total absence are known. Although fascioles are widely used in the classification of spatangoids, diversity of fasciole tuberculation has largely been ignored. We examine fascioles in about 100 spatangoid species, focusing on the earliest manifestations of fascioles (both developmentally and phylogenetically) and on their variable tuberculation. Qualitative observations are complemented by quantitative analyses (ANOVA and PCA) of 21 species. Three types of fascioles are defined according to tubercle pattern: protofascioles for localized concentrations of miliaries; parafascioles for bands of miliaries with a progressive transition to the surrounding tuberculation; orthofascioles for strongly differentiated, well-circumscribed bands of miliaries. Ontogenetic, architectural, ecological, and taxonomic variations of these three patterns are qualitatively and quantitatively investigated. We attempt to delineate plausible homologies, origins, and subsequent evolution of the different kinds of fascioles.

Development of the bitterling,Paracheilognathus himantegus (Cyprinidae), with a note on minute tubercles on the skin surface

Development of the bitterling,Paracheilognathus himantegus (Cyprinidae), with a note on minute tubercles on the skin surface

Endocochliate embryo model in the Mesozoic Ammonitida

An endocochliate embryo model for the Mesozoic Ammonitida is proposed based on scanning electron microscopy of the ammonitella (= embryonic shell) stage of well‐preserved Japanese Cretaceous specimens belonging to nine species of five superfamilies. As in other specimens described previously, the ammonitella wall succeeding from the initial chamber ("protoconch") in the species examined consists of the inner prismatic, middle subprismatic and outer prismatic layers, with minute tubercles resting on the outer. Developmental patterns of these structures and their comparison with primary shell formation in modern Nautilus and Spirula suggest that the outer thin prismatic layer with microtubercles was secreted by the exterior epithelium after the completion of the main ammonitella wall by the interior shell gland. Thus, the early ammonite embryo might have had an endocochliate structural plan as in coleoids, and at the time of hatching the overlying mantle epithelium had shifted anteriorly to become an ectocochliate condition.

Development of the bitterling,Tanakia tanago (cyprinidae), with a note on minute tubercles on the skin surface

The development of eggs and larvae and minute tubercles on the skin surface in larvae ofTanakia tanago were observed. The eggs began to hatch approximately 52 hours after insemination and the larvae reached free-swimming stage 19 days after hatching at water temperature of 22±1°C. The egg and larval development and minute tubercles on the skin surface in larvae of this species were similar to those ofAcheilognathus lanceolata andA. limbata. However,T. tanago was distinguishable in egg and larval development fromA. lanceolata andA. limbata by the following characters: the perivitelline space was narrower, embryonic and larval development was faster, and minute tubercles on the skin surface of the anteriormost parts of the yolk sac, and of the body and head were hemispheric in shape. From these characters,T. tanago is considered to be more specialized thanA. lanceolata andA. limbata.

Minute tubercles on the skin surface of larvae ofAcheilognathus andPseudoperilampus (Cyprinidae)

It is known that bitterling larvae ofAcheilognathus andPseudoperilampus have minute scalelike tubercles on the skin surface (Uchida, 1937, 1939; Nakamura, 1969). Recently Fukuharaet al. (1982) described minute scaly tubercles distributed on the surface of the yolk sac in the larvae ofAcheilognathus. However, they did not mention the minute tubercles distributed on the skin surface of the whole body and morphological changes of the tubercles with growth of the larvae.

Effect of Soil Moisture on Oviposition, Water Absorption, and Survival of Southern Masked Chafer (Coleoptera: Scarabaeidae) Eggs1

Eggs of Cyclocephala immaculata Olivier absorb water from the soil, increasing ca. threefold in weight during the first 10 days of embryonic development. Eggs developed normally at soil moistures of 12.5% and above, but shriveled and died in drier soils. Length of incubation period, survival, and final egg weight did not differ at soil moistures within the range required for survival; however, few eggs were laid in dry soil or when soil moisture approached field capacity. Oviposition in soil moisture gradients indicated that the depth at which eggs are laid can vary in response to moisture levels. The chorion of the egg is covered densely and uniformly by minute tubercles, but specialized hydropyles are absent. The eggs are most susceptible to desiccation when newly laid or close to hatching, but are relatively resistant during the middle stage of development. These differences are associated with changes in the thickness of the serosal cuticle.

The Occurrence of Oestrus ovis L. (Diptera: Oestridae) in the Bighorn Sheep from Wyoming and Montana

Three previous and five new records of the domestic sheep bot, Oestrus ovis, from the bighorn sheep are given. The life history and descriptions of adult and larval forms are presented. The significance of the occurrence of the parasite in the abnormal host is discussed. The infrequent occurrence of an aberrant parasite in an abnormal host is ordinarily of particular interest only to specialists acquainted with these groups. Repeated occurrences, however, may have a special biological significance particularly when they are found in related hosts occupying similar habitats. This could well be the case of the domestic sheep botfly, Oestrus ovis L., as it is found in bighorn sheep, Ovis canadensis Shaw, in North America. The parasite normally occurs in domestic sheep, Ovis aries, and goats, Capra hircus, in almost every sheep-raising district in the world. It is found generally throughout the United States and Canada and is considered one of the most important pests of domestic stock. While in flight the female fly deposits a small droplet containing two or three minute larvae in the nostrils of the selected host. These first-instar larvae migrate into the nasal passages and remain 1 to 9 months, feeding on the mucous exudate caused by their constant irritation of the mucosa. Cobbett and Mitchell (1941) report that the second-instar larvae then migrate into the frontal sinus, where development is accelerated. When the third stage is completed the larvae migrate out through the nostrils and drop to the ground to seek a suitable medium for pupation. The pupal period varies considerably according to the climatic conditions and season, but averages about 6 weeks. The adult flies mate shortly after emergence and the gravid female seeks out the hosts to deposit her larvae. Mature, gravid females will produce an average of 500 larvae within their life span of 2 or 3 weeks. The adult flies frequently cause considerable annoyance when attacking the host animals. Received for publication 1 November 1965. Domestic sheep become terrified when approached by the loud-buzzing insect and will often bunch together with their heads inward and held close to the ground. Others may run frantically, shake their heads, or suddenly push their muzzles against the ground or between other sheep. The migration of the larvae over the delicate membranes causes the animal to rub its nose on the ground and to strike sharply with its forefeet. Infected sheep usually have a pronounced nasal discharge, sneeze frequently, and grate their teeth. Loss of appetite is common, emaciation follows, and death is not unusual in severe cases. According to Cobbett and Mitchell (1941) inflammation of the mucosa is always associated with the presence of dead larvae, and secondary bacterial invasion is probably the cause of death. DESCRIPTION OF ADULT The adult female fly measures approximately 11 mm in length. The overall color is dark gray with the exception of the head and legs, which are dull yellow. The parafrontal areas are a series of deep, pock-like depressions containing numerous thin hairs. The mouthparts are vestigial and are reported to be nonfunctional although it is possible that the adult fly may take in moisture during its brief mating period. The thorax is a frosted gray with four black, parallel stripes composed of numerous minute tubercles, each bearing a hair. The legs are yellow with moderately strong bristles on each tarsal segment. The wings are hyaline and membranous, approximately 8.0 mm in length with minute spinules the entire length of the costal vein. The abdomen is usually black with an irregular pattern of gray pollinose spots. DESCRIPTION OF LARVAE The first instar (Fig. 1) is tapered at both ends and measures about 1.0 mm in length. The oral hooks are heavily sclerotized, black, and strongly recurved. The hooklets located on the caudal segment (Fig. 2) are diagnostic for the species. Two terminal protuberances each support 10 or 11 of these hooklets, which are best viewed from the

The Structure and Development of the Larval Cuticle of Diataraxia oleracea (Lepidoptera)

ABSTRACT The main layers comprising the soft cuticle of the Diataraxia larva have been defined and a study made of their formation during development of the 5th instar larval cuticle. In soft cuticle the epicuticle is thrown into minute tubercles and consists of three layers—the cuticulin layer, the wax layer, and the cement layer. The cement layer lies outside or partly embedded in the wax layer, but it is either absent or extremely thin over the tips of the tubercles. A polyphenol layer is absent and it is suggested that this layer is present only in hard cuticle. Beneath the epicuticle is a thin, lightly tanned exocuticle approximately 0.5µ thick. The 7-10p. thick outer endocuticle is perforated by well-defined pore canals and consists of lamellae containing chitin fibres varying from 100 to 2,000 A in diameter. Pore canals are absent in the inner endocuticle which when fully developed may be more than 5oµ in thickness. At 25° C., moulting of the 4th-5th instar takes less than 48 hours. The cuticulin layer is laid down about 12-24 hours before ecdysis. At about 6-12 hours before ecdysis the exocuticle is formed beneath the cuticulin layer in the outer part of the developing outer endocuticle. Formation of the wax layer begins about 1 hour before ecdysis, while the cement layer is secreted only a few minutes prior to ecdysis. The inner endocuticle is laid down during the 5 days after ecdysis. Prior to ecdysis the pore canals connect the hypodermis to the epicuticle and open into the exuvial cavity at the tips of the epicuticular tubercles. Probably the pore canal lumen is responsible for conduction of the moulting fluid. Each pore canal contains a well-defined strand of material which occupies but a small part of the pore canal lumen. Thè pore canal strands, conduct protein and dihydroxyphenol from the hypodermis to form the exocuticle. Exocuticle formation is complete by about 112 days after ecdysis. At this stage the pore canal strands become chitinized and sclerotized and the pore canals are cut off from the hvpodermis by the developing inner endocuticle. The pore canals are not responsible for transport of regenerative waxes from the hypodermis after abrasion of the epicuticle. In areas of hard cuticle there is a relatively thick and heavily tanned exocuticle which continues to develop during the life of the instar. The pore canals maintain contact with the hypodermis throughout the instar and probably remain functional as a conducting system for transport of exocuticular materials. A study of Verson’s glands suggested that the large gland cell secretes a lipoprotein which is discharged on the surface of the epicuticle to form the cement layer. The intercalary cell secretes a phenol which is responsible for the tanning of a plug that blocks the opening of the gland duct after discharge.

Observations on scale-insects (Coccidae)—III

Female, adult. More or less circular or faintly pentagonal ; low convex ; pseudo-margin strongly rounded, giving the insect a markedly “crustliform” (Green) appearance ; margin very thin and shallow ; anterior stigmatic clefts well defined. Dorsum with a slightly subcentral depression, from which there arise strong radial striae extending to the pseudo-margin. Anal cleft fused. Anal lobes in the subcentral depression, so that they appear almost in the middle of the back. Colour of dorsum brownish black, with minute reddish-buff glandular spots. Venter coffee-brown. Detached scurfy particles of a somewhat glassy secretion within the pseudomargin, and six larger particles of similar material, each resting upon a minute tubercle, arranged in a parallelogram near the central depression. Derm cells closely packed together, very irregular in shape, many being markedly attenuated at one extremity; these are divided into more or less definite radial bands corresponding to the spaces between external striae; in the central area of the dorsum they are almost obscured by the dense chitin, so that only the minute central pores are traceable; in this same area are a number of larger and clearer pores varying considerably in size, the larger ones radiating from the anal lobes.

ULERYTHEMA SYCOSIFORME (LUPOID SYCOSIS) WITH REPORT OF TWO CASES.

The following report is deemed worthy of presentation on occount of the rarity of the disease and the obscurity that has until recently surrounded it. About 1865 the disease was described by Milton under the name lupoid sycosis. This author says I have seen in some rare cases (of sycosis) a slow superficial form of ulceration beginning with minute tubercles and attacking the hair follicles causing falling of the hair and slight though indelible cicatrices, a disorder which seems to me to be nothing more than lupus non-exedens. Unna, in 1889, described a disease which he termsulerythema sykosiformeand reports a case in considerable detail. By ulerythema the latter writer means a pathologic process which goes on to the formation of atrophic scars without intermediate suppuration or ulceration; in other words, through the resorption of the cellular infiltrate. We append a full record of the case reported by Unna

Stridulating Organs in Scorpions

AT the September meeting of the London Entomological Society, Mr. J. Wood-Mason announced the discovery of tridulating organs in scorpions. While recently working at the anatomy of a species allied to S. afer, he had met with structures which, from his familiarity with the analogous ones in other arthropods, crustaceans as well as insects, he had at once without hesitation determined to be sound-producing apparatus—even before he had found that sounds could be produced by them artificially by rubbing the parts together or accidentally in the mere handling of alcoholic specimens. He had, however, been enabled to place the matter beyond all doubt, for while at Bombay waiting for the steamer, he had obtained, by a happy chance, from some Hindustani conjurors, two large living scorpions belonging to another species of the same type; these, when fixed face to face on a light metal table and goaded into fury, at once commenced to beat the air with their palps and simultaneously to emit sounds which were most distinctly audible not only to himself, but also to the bystanders, above the clatter made by the animals in their efforts to get free, and which resembled the noise produced by continuously scraping a piece of silk woven fabric, or, better still, a stiff tooth-brush with one's finger-nails. The species—a gigantic one from the Upper Godaveri district—in which he had first observed stridulating organs, had these organs more highly developed than in the one experimented upon nt Bombay, and must stridulate far more loudly, for by artificially rubbing the parts together in a dead alcoholic specimen he could produce a sound almost as loud as, and very closely similar to, that made by briskly and continuously drawing the tip of the index-finger backwards and forwards in a direction transverse to its coarse ridges, over the ends of the teeth of a very fine-toothed comb. The apparatus, which, as in the Mygale, is developed on each side of the body, was situated—the scraper upon the flat outer face of the basal joint of the palp-fingers; the rasp on the equally flat and produced inner face of the corresponding joint of the first pair of legs. On separating these appendages from one another, a slightly raised and well-defined large oval area of lighter coloration than the surrounding chitine was to be seen at the very base of the basal joint of each; these areæ constituted respectively the scraper and the rasp; the former was tolerably thickly but regularly beset with stout, conical, sharp spinules curved like a tiger's canine, only more towards the points, some of which terminate in a long limp hair; the latter crowdedly studded with minute tubercles shaped like the tops of mushrooms. He had met with no stridulating organs in this position in any scorpions besides S. afer and its allies; but in searching for them in other groups he had come to the conclusion that the very peculiar armature of the trenchant edges of the palp-fingers in all the Androctonoidæ, and in some at any rate of the Pandinoidæ (no Telegonoidæ or Vejovoidæ had yet been examined), was nothing but a modification for the same purpose, for the movable finger of this pair of appendages when in the closest relation of apposition to its immovable fellow could most easily be made to grate upon it from side to side so as to produce a most distinct crepitating sound; but when separated from it ever so little appeared to be incapable of the slightest lateral movement. It was his intention on his return to India to endeavour to determine this question, as well as many others relative to the species in which the presence of sound-producing apparatus had now been demonstrated by careful observation and experiment upon living animals.

On the Occurrence of the Genus Astrocrinites (Austin) in the Scotch Carboniferous Limestone Series; with the Description of a new Species ( A. Benniei ), and Remarks on the Genus

I ntroduction .–In a paper entitled “Proposed Arrangement of the Echinodermata” &amp;c., Messrs. Austin referred to a genus which they proposed to establish under the name of Astracrinites , in the following words:—“Another genus ( Astracrinites of our MS.) offers so many affinities to the recent and fossil Echinodermata, that we consider it the most remarkable of all the known genera. By its being lobed it approaches to the Lobistella ; its ambulacra, spines, and arms mark it as allied to the Echinites , while the arrangement of its calcareous plates connects it with the Lilies of the ocean. In short, it possesses the lobes of a Starfish, the ambulacra and spines of a Sea-urchin, and the plates of a Crinoid. It is further remarkable by deviating from the quinary type so prevalent in the Echinodermata: the lobes and ambulacra of this new genus are each four in number.” In the following year Messrs. Austin described this curious and aberrant form under the name of Astracrinites tetragonus. Their description is as follows :” “Family Astracrinidæ, “Consisting of the genera Astracrinites and Aporocrinites ; “Genus Astrocrinites, Austin. “Def.—Dorso-central plate quadrangular, to which four pairs of elongated plates are attached, imparting a lobed shape to the fossil. In the retiring angles at the base of the four lobes are a like number of ambulacra. Mouth central. Anus lateral. “A. tetragonus, Austin. “Def.—The plates of this species agree with the generic definition. Each of the elongated plates has two or three rows of minute tubercles around its outer margin

VI.—On Some of the Massive Forms of Chætetes, from the Lower Silurian

The typical forms of Chœtetes petropolitanus, Pander, are free in habit, and are invariably furnished with a flattened or concave base, which is covered with a thin concentrically-wrinkled epitheca. The general shape of the corallum is typically a cone or hemisphere when full-grown, and a concavo-convex disc when young; but its adult form is liable to great variations; and even the young examples are not constant, being sometimes plano-convex, or slightly bi-convex. The calices are exclusively carried upon the upper surface of the mass, and are thin-walled, polygonal in shape, and destitute of intermediate tubuli. Very often the surface exhibits minute tubercles, carrying corallites of a slightly larger size than the average; but this phenomenon does not appear to be constant. Young examples may have a diameter at their base of four or five lines, and a height of three lines; adult specimens may have a long diameter of four inches or more at the base, and a height of an inch and a half; but the majority of individuals exhibit dimensions intermediate between these measurements.

Note on some Ichthyosaurian Remains from Kimmeridge Bay, Dorset

These remains consist of several teeth and of fragments of a skull transmitted to me for examination last summer by J. Mansel Pleydell, Esq., F.G.S., to whom I have been already indebted on several occasions for opportunities of bringing under the Society's notice Saurian fossils from the Dorsetshire Kimmeridge beds. Unfortunately, as so commonly happens when the extrication of fossils from the shale is attempted by unskilled labourers, the bones were smashed into so many pieces as to render the restoration of the skull quite impossible. Estimated by the size of the broken pieces, the snout was probably not less than three feet long, and it was proportionately stout. Of the teeth some are shorter, more curved, and relatively stouter than the others. In both forms the crown is bluntly pointed, its base passes evenly into the root without any separating cingulum, and the proximal end of the root is laterally compressed, which gives its cross section an oblong figure (fig. 8), the longer sides of which are parallel with those of the dentary groove. The crown is strongly striated; the striæ diminish regularly from the base to the apex, near which they break up into lines of minute tubercles, which are continued to the very extremity. The most perfect of the longer teeth (only the extreme tip of the crown of which is missing) is 30 1/6 lines (English long, of which the crown forms 8 1/6 lines (figs. 1-3). The base of