NO. 10 DAWSON : MARINE ALGAE, GULF OF CALIFORNIA 209 



Dec; D. 613b, in oyster-culture pond, San Gabriel Bay, Espiritu Santo 

 Island, Feb. 



Genus CLADOPHORA Kiitzing 

 Gladophora Rudolphiana (Ag.) Kiitz. 



Kiitzing, 1843, p. 268; Harvey, 1846-51, pi. LXXXVI; Collins, 1909, 

 p. 336; Setch. & Gard., 1920, p. 218; Taylor, 1937, p. 87, pi. 5, 

 figs. 2-4, pi. 6, fig. 2. 



Two collections which show main filaments about 50 /x in diameter 

 and with very long cells fall best into this old European species reported 

 by Collins and by Taylor from the east coast of North America. Setchell 

 and Gardner, 1920, do not report having seen any specimens comparing 

 with the typical species from the Pacific coast, but give Cladophora Ru- 

 dolphiana f. eramosa Gardner. D. & R. 3273 is more like this lax form, 

 having longer, simpler branches than D. & R. 3425a, which corresponds 

 rather well with Collins' description and with Harvey's figures. Our 

 specimens are not of large plants ; D. & R. 3275 is up to 5 cm. high. 



D. & R. 3273, on rocks in tidal creek near Guaymas, Dec. ; D. & R. 

 3425, attached to drifting Gracilaria, Empalme, Dec. 



Gladophora microcladioides Collins 



Collins, 1909a, p. 17, pi. 78, figs. 2, 3; Setch. & Gard., 1920, p. 212, 

 pi. 13, fig. 2. 



Several collections of this distinct species have recently been made in 

 the Gulf and extend the range of this plant still farther south on the 

 Pacific coast. The figures of Collins and of Setchell and Gardner are 

 sufficient to identify it, the curved secund ramuli easily setting it apart 

 from others of our region. Plants of different collections vary consider- 

 ably in size and diameter. 



This species is sublittoral in the Gulf, no specimens being known from 

 shore stations except as drift. 



D. 147, in 4-32 meters off Tiburon Island, Jan.; D. 348, in 22 me- 

 ters, Punta Penasco, Feb.; D. 51, in 3-4 meters, Guaymas Bay, Jan.; 

 D. 380, in 22 meters, Tepoca Bay, Feb.; D. & R. 2928, washed up on 

 beach. Kino, Nov. 



Gladophora albida (Huds.) Kutz. 



Kiitzing, 1843, p. 267; Harvey, 1846-51, pi. CCLXXV; Collins, 1909, 

 p. 336. 



