NO. 2 DAWSON : MARINE RED ALGAE OF PACIFIC MEXICO 243 



Dermocorynidaceae 



With a single species in the Mexican flora. 

 Dermocorynus occidentalis Hollenberg 



Hollenberg 1940, p. 868, figs. 1-6. 



The following is a quotation of Hollenberg's original description: 

 "Plants forming thin, brownish red, horizontally expanded thalli, 1-3 

 cm. diam., bearing numerous erect simple fruiting branches 1-2 mm. 

 high; basal thallus 50-100-(170) /i, thick, composed of erect filaments of 

 cells mostly 4-6 /* diam. and sometimes grading into a more or less evi- 

 dent hypothallus of several layers of larger horizontally elongate cells; 

 fruiting branches usually simple, narrowed at the base, and composed of 

 longitudinal branching medullary filaments and forking anticlinal corti- 

 cal filaments ; tetrasporic branches somewhat flattened ; cystocarpic 

 branches cylindrical or somewhat flattened; tetrasporangia 12-16 x 22-26 

 [I, scattered over the entire surface of the fruiting branches, cruciately 

 divided; cystocarps one to several, 90-130 jx diam., embedded in the erect 

 branches, often bulging, but without pore or perithecium; carpospores 

 10-15 ju. diam., in a dense globular mass." 



Type: Holotype not designated. Tetrasporic and cystocarpic syn- 

 types are represented respectively by numbers 650, Feb. 2, 1935, and 

 2408, Dec. 8, 1938, in the herbarium of G. J. Hollenberg, University of 

 Redlands, California. 



Type locality: Emerald Bay, Laguna Beach, California. 



Mexican distribution: Pacific Baja Calif. — Punta Banda (spec- 

 imen in Herb. Hollenberg). 



No new material has been examined and nothing more can be added 

 at this time to Hollenberg's thoroughgoing account of this species and 

 of the family Dermocorynidaceae. 



Grateloupiaceae 



Key to the Mexican Genera 



1. Thalli parasitic on Zanardinula, small, pulvinate . . . 



Lobocolax p 



1. Thalli not parasitic 



2. Medulla prominent, densely stuffed with ramified fila^ 

 ments; tetrasporangia in nemathecial sori 



286 

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