Erect Axes Research Articles

A Revised Classification of the Leucodontaceae and a Revision of the Subfamily Alsioideae

A reclassification of the Leucodontaceae recognizes four subfamilies and three tribes: Alsioideae (Fleisch.) Broth. emend. Manuel; Felipponoideae Manuel, subfam. nov.; Forsstroemioideae Manuel, subfam. nov.; Leucodontoideae, Dozyeae Manuel, tribus nov., Leucodonteae, and Pterogonieae Fleisch. emend. Manuel. A key to the subfamilies and tribes is presented. Alsia Sull. and Dendroalsia Britt., two monotypic genera endemic to western North America which constitute the subfamily Alsioideae, are reviewed. Descriptions, illustrations, distribution maps, and a key to the genera are presented in addition to notes on phytogeography and nomenclature. Alsia californica var. flagellifera Ren. & Card. is reduced to the synonymy of A. californica (Hook. & Arnott) Sull. Alsia macounii Kindb. ex Broth., Dendroalsia donna Britt. ex Fleisch., and Leptodontis Sull. ex Broth. are nomina nuda. Lectotypes for Neckera californica Hook. & Arnott and Neckera abietina Hook. are designated. Dendroalsia abietina (Hook. & Arnott) Britt. is reported new to Alaska and tentatively to Colorado. As part of an ongoing study of the Cryphaeaceae (Manuel, 1973a, b) I decided to review the monotypic genera Alsia Sull. and Dendroalsia Britt., since the two are historically entwined nomenclaturally. However, during the course of the investigation doubt arose as to the validity of retaining the two genera, along with Forsstroemia Lindb. and Bestia Broth., within the Cryphaeaceae. Thus, an investigation was undertaken to delimit both the Cryphaeaceae and Leucodontaceae. The results of that study, in part [the affinity of Hydrocryphaea Dix. with the Cryphaeaceae is the subject of another paper (Manuel, 1975)], are presented herein. In order to avoid the use of the terms primary and secondary stem, I have herein adopted, in part, the terminology used by Argent (1973). The term shoot is used for the creeping axis which gives rise to erect axes called stems. In the case of Dendroalsia, the consists of an unbranched lower portion called the and a branched upper portion referred to as the (Touw, 1971, pp. 213-214). In Alsia, neither stipe nor frond is differentiated, but 1 Contribution No. 119 from the Department of Biology, The Pennsylvania State University. I thank Dr. Ronald A. Pursell for his guidance and critical help with the manuscript, Drs. Robert W. Carrubba and Joseph C. P. Cotter of the Department of Classics for their linguistic advice, and the curators of the herbaria cited in the text for the loan of specimens. 2 The Herbarium, Department of Biology, The Pennsylvania State University, University Park, Pennsylvania 16802. This content downloaded from 157.55.39.105 on Fri, 07 Oct 2016 04:49:19 UTC All use subject to http://about.jstor.org/terms 532 THE BRYOLOGIST [Volume 77 instead, short unequal branches occur irregularly along the stem. The term flagelliform branch is used for those axes which arise from the stem or branches, or both, and which upon reaching the substrate act as stoloniform shoots. Argent (1973) used the term prorate to describe the occurrence of cell ends which project from the surface of the leaf. He pointed out that a papilla is an extension of the cell wall, and thus the terms papilla, papillose, and papillate are not applicable. I use the term prorula (Gr., little prow) to refer to an individual projecting cell end. The corresponding terms prorulose, prorulate, and prorulosity are also used. Specimens examined during the course of this investigation were from the following herbaria: CANM, DUKE, FH, H, HSC, MICH, NY, PAC, S-PA, UAC, UBC, UC, Us, and wru. Measurements, observations, and drawings were made from specimens mounted in Hoyer's Solution (Anderson, 1954). A REVISED CLASSIFICATION OF THE LEUCODONTACEAE

The life history ofPetrocelis franciscana

Tetraspores from Petrocelis franciscana Setch. et Gardn. collected at Rockaway Beach, San Mateo County, California, 11 January 1971 were isolated into unialgal culture with Provasoli's enriched seawater medium at 10° and 15° C, 16:8 daily photoregime, 2000–2500 lx cool white fluorescent lighting. The germlings developed as crustose discs with marginal meristems until about 300–500 µm in diameter when erect multiaxial blades were established. The erect plants grew to reproductive maturity in 15° C but not in 10° C. By the fifth month of growth the erect axes flattened and branched dichotomously. At the end of 7 months the plants were reproductively mature. These cultured plants were morphologically similar to Gigartina agardhii Setch. et Gardn. (subgenus Mastocarpus) which occurs abundantly at Rockaway Beach. Male plants were non-papillate with spermatangia forming on the entire blade surface except at the growing tip and near the stipe. The female plants developed papillae which bore many procarps. Many o...

Observations on Pseudobryopsis and Trichosolen (Chlorophyceae-Bryopsidaceae) in America

Oltmanns (1904, p. 303) credits Berthold with the separation of Pseudobryopsis from Bryopsis on the basis of the presence of specialized gametangia and the segregation of the ramelli by a basal wall. The species from Naples which he knew, P. myura (J. Ag.) Berth., only occasionally has the erect axes branched, has simple ramelli neither markedly curved nor particularly swollen