228 University of California Publications in Botany [Vol. 8 



loc. cit. (fide Yeiido). Cladophora Mertensii De-Toni, Syll. Alg., 

 vol. 1, 1889, p. 317. Cladophora riminca De-Toni, loc. cit., p. 318. 

 Spongomorpha arcta var. limitanea Collins, Green Alg. N. A., Suppl. 

 I, 1912, p. 97, in Collins, Holden and Setchell, Phyc. Bor.-Anier. 

 (Exsiec), no. 1736. Acrosiphonia Mertensii (Riipr.) Yendo, Notes 

 on algae new to Japan, V, 1916, p. 246. 



Collins (1909, p. 360), on evidence furnished by authentic speci- 

 mens in Herbarium Farlow, unites not only Canferva Mertensii Rupr. 

 with C. viminea Rupr., but also unites with them C. Chamisso)iis 

 Rupr. and C. saxatilis Rupr., placing all these names as sj'nonj-ms 

 under Spongomorpha saxatilis. Yendo (1916, p. 245), however, as a 

 result of study of the type specimens preserved in the Herbarium of 

 the Imperial Academy of Sciences of St. Petersburg, is of the opinion 

 that Conferva saxatilis and C. Chaniissonis are simply forms of one 

 species and that C. Mertensii and C. viminea are also forms of one 

 species, but that the two latter are quite distinct from the two former. 

 Yendo does not, however, point out in what this difference consists. 



We are inclined to refer here provisionallj' and with considerable 

 doubt, a specimen (no. 3288 of Setchell and Lawson) collected at 

 Amaknak Island in the Bay of Unalaska. It is somewhat coarser than 

 specimens of Spongomorpha saxatilis and of even more lax habit. It 

 has no spines, but has occasional inrolled, circinate, yet blunt, branch- 

 lets, very different, however, from the hooked branches of either of 

 the two succeeding species. The general aspect, the dimensions, and 

 these inrolled branchlets are all indicated in Ruprecht's description 

 of Conferva Mertensii and assist in distinguishing this species from 

 C. saxatilis. 



Very similar to the Unalaska plant is that distributed under 

 no. 1736 of the Phycotheca Boreali-Americana. It has no spiny 

 branches or branchlets but it usually shows circinate, often branched, 

 branchlets. The terminal segments vary from verj^ blunt and dilated 

 to extremely attenuated and in some plants are prolonged into curious 

 long and sinuate rhizoids. The last character has been noticed only in 

 summer plants. We may add that the description of this species has 

 been drawn up largely from our Califomian specimens. 



The type locality for Conferva Mertensii Rupr. is given as Sitka, 

 while C. viminea Rupr. is given as occurring at both Sitka and 

 Unalaska. 



