NO. 10 DAWSON : MARINE ALGAE, GULF OF CALIFORNIA 211 



A fragmentary specimen from La Paz, in the Herbarium of the New- 

 York Botanical Garden, ex. herb. C. L. Anderson, was doubtfully identi- 

 fied with this species by M. A. Howe. It was not considered worth while 

 to re-examine this specimen. The record must remain a questionable one 

 for our area until confirmed by ample material. 



Cladophora MacDougalii Howe 



Howe, 1911, p. 491, pi. 3,3, fig. 7; Collins, 1912, p. 96; Setch. & Card., 

 1920, p. 214. 

 The type specimen was taken in San Felipe Bay by D. T. MacDougal 

 in February, 1904. No specimens referable to this species have appeared 

 in recent collections. Collins considers it very near to or the same as Cali- 

 fornia specimens of Cladophora ovoidea, but Setchell and Gardner prefer 

 to consider the two distinct. From other Gulf species it is said to be dis- 

 tinguished by its rather large diameter, 135-310 fi in main branches, 75- 

 110 ju, in ultimate lateral ramuli, and by its short cells, mostly 1.5-2.5 

 times as long as broad, somewhat constricted at the septa. 



Cladophora hesperia S. & G. 



Setch. & Gard., 1924, p. 713, pi. 13, fig. 17. 



A comparison of D. 653 with the type of this species indicates that the 

 two are the same. The plants collected by the writer were, like the type, 

 growing in a dense, thin mat on rock surfaces. They are 1-1.5 cm. high, 

 abundantly branched, and in all respects conform to the description and 

 illustration given by Setchell and Gardner. 



Brand. 21, growing in muddy habitat at the southern extremity of 

 Lower Calfornia; D. 653, on middle littoral rock surfaces, rocky point 

 north of Kino, July. 



D. 602f from San Gabriel Bay, Espiritu Santo Island, is only a scrap 

 of a specimen but perhaps should be referred here. It is more lax than the 

 typical species but is of the same size and habit. 



Cladophora tiburonensis sp. nov. 

 Plate 31, Figs. 1-3 



Frondes caespitosae, 3-4 mm. altae, matta fibrarum multicellularum raraos- 

 arum affixae; filis erectis superne circa 25 \i diam., stricte, subdichotomo usque ad 

 secundo ramosis; cellulis 4-5 plo. diam. longioribus; zoosporangiis circa 40 x 70 n 

 amplis. 



