NO. 2 DAWSON: MARINE RED ALGAE OF PACIFIC MEXICO 263 



and 30-65 /x long, these mostly longitudinally arranged ; antheridia borne 

 in a superficial sorus consisting of an incomplete reticulum of sterile cells 

 separating groups of fertile cells. 



Type; Holotype is Dawson 85-40, Jan. 23, 1940, on sheet 34 in 

 HAHF. 



Type locality : On bottom of broken shell and mud at a depth of 

 12-20 m. just outside the harbor of Bahia Guaymas, Sonora, Mexico. 



No new material of this species has been obtained, but reexamination 

 of the type collection has revealed an antheridial plant. This mature 

 sexual plant happens to be the one which was illustrated on plate 45 in 

 the original publication. 



The close relationship between this plant and Cryptonemia angustata 

 (Setchell & Gardner) Dawson has previously been suggested. Since 

 it is felt that the species will most readily be recognized in that rela- 

 tionship, the transfer to Cryptonemia is made despite the lack of carpos- 

 poric material. The small mature size and early splitting and progressive 

 laceration of the blades are distinctive of this plant. The small specimens 

 are about twice as thick as comparable examples of C. angustata. 



Cryptonemia guaymasensis (Dawson) comb. nov. 



Callymenia guaymasensis Dawson 1944, p. 286, pi. 68, fig. 2. 



A small fragmentary specimen dredged from Bahia San Lucas, Baja 

 California and bearing cystocarps has satisfactorily been matched by 

 means of its vegetative structure with the type and other sterile specimens 

 of Callymenia guaymasensis. The cystocarps are characteristic of the 

 Grateloupiaceae and require the transfer of the species to that family. 

 The vegetative structure agrees with that of Cryptomenia. The presence 

 of refractive filaments in the medulla similar to those of Cryptonemia 

 obovata and other species is also suggestive of the propriety of this dis- 

 position. 



Cryptonemia guaymasensis occurs both intertidally and in the sub- 

 littoral, and exhibits in these different habitats some differences in habit 

 and structure. 



Thalli 5-7 cm. high and often as broad, deep rose red in color, ap- 

 parently perennial under some conditions, consisting of one or more short 

 (2-5 mm.), compressed or subcylindrical stipes attached by a discoid 

 holdfast and supporting dissected, branched, flat, membranous blades; 

 stipe in intertidal plants proceeding into the base of the blade as a mid- 

 rib and sometimes continuing to the first dichotomy; sublittoral plants 



