NO. 1 DAWSON : MARINE RED ALGAE OF PACIFIC MEXICO 127 



Thalli saxicolous, 3-10 (15) cm. high, consisting of several to many 

 axes from a crustose basal stratum, the erect parts densely congested, 

 loosely tufted, or elongated, loose and limp ; lower intergenicula of axes 

 subcylindrical, usually about .75 mm. broad and to 1 mm. long; upper 

 axial intergenicula compressed, cuneate, mostly 1 mm. in greatest dia- 

 meter; branching pinnate-opposite, distichous to verticillate, the pinnae 

 simple, lobed or segmented and in turn pinnate or digitate, reduced to 

 about half the diameter of the main axial intergenicula, or sometimes 

 reduced much more, to 1/10 that diameter; lateral branchlets indeter- 

 minate, divergent and confused, or more or less uniformly determinate 

 and appressed; conceptacles terminal, appearing pedicellate on slender 

 ultimate pinnae, ovoid, entirely or mainly non-antenniferous. 



Type : Holotype not designated. Syntypes of Yendo's collection, if 

 extant, probably to be found in the Botanical Institute of the University 

 of Tokyo, Japan. 



Type locality: Port Renfrew, British Columbia, Canada. 



Distribution: Variants of this polymorphic species are widely 

 distributed along the North American coast from southern British 

 Columbia to southern Baja California. They often are extremely abund- 

 ant and dominant as intertidal rock-cover inhabitants and, especially in 

 the southern half of the range, as the principal element of the intertidal 

 turf in which case they are usually markedly dwarfed. Well-developed 

 plants usually are to be found in tide pools, although sometimes nearly 

 pure stands of var. lycopodioides may be found on exposed surf-beaten 

 rocks. 



In some heavily reproductive collections, as those from Cardif, Cali- 

 fornia, the conceptacles may be in part rather conspicuously antenni- 

 ferous. Even in these cases, however, the non-antenniferous character is 

 dominant, and although the aspect may resemble that of CoralUna 

 gracilis quite closely, the plants are somewhat coarser in all respects. 



The nomenclature of this eastern Pacific species has been badly con- 

 fused. For the most part, the plants which are recognized here have more 

 recently been known as Corallina gracilis var. densa Collins. The type 

 of that plant, however, Phyc. Bor. Amer. no. 650, has non-antennifer- 

 ous conceptacles, and thus, following Manza, 1940, does not belong 

 with C. gracilis in the subgenus Cornicularia. The earliest name for a 

 Pacific American non-antenniferous Corallina, and the one under which 

 we may recognize the present species, is Corallina vancouveriensis 

 Yendo. A comparison of Yendo's illustration and of specimens from the 

 Puget Sound area with series of plants from California and Baja Cali- 



