494 University of California Puhlications in Botany [Vol. 6 



Hormiscia vancouveriana (Tilden) Setchell et Gardner comb. nov. 



Urospora WormsMoldii Setchell & Gardner, Alg. N. W. Amer.. 

 1903, p. 221 (in part). Hormiscia Wormskjoldii Collins, Green Alg. 

 N. A., 3909, p. 368 (in part). Urospora Wormskjoldii f. vancouveriana 

 Tilden. Amer. Alg. (Exsicc.) no. 381. 



Comparison of Miss Tilden 's plant with material of Urospora 

 Wormskioldii (Mert.) Rosenv.. collected by J. Vahl in May, 1831, 

 at Godthaab, Greenland, the type locality, has convinced us that her 

 Vancouver Island plant is a distinct species, based chiefly upon the 

 following differences: (1) much larger segments, up to 3mm. in 

 diameter; (2) a much more dense chromatophore with smaller open- 

 ings; and (3) the mature segments much more nearly spherical. 



Hormiscia grandis (Kylin) Setchell et Gardner comb. nov. 



Plate 42, fig. 3 



Growing on rocks in the upper littoral belt. West shore of 

 Amaknak Island, Bay of Unalaska, Alaska. No. 3279 (Herb. Univ. 

 Calif, no. 98535), Setchell. 



Urospora penicilliformis Setchell & Gardner. Alg. N. "W. Amer., 

 1903, p. 220 (in part). Urospora grandis Kvlin, Studien ueber Algen- 

 flora, etc., 1907, p. 18, fig. 3. 



Number 514 (Herb. Univ. Calif, no. 98533), Gardner, collected in 

 May, 1899, at Esquimalt, British Columbia, seems also to belong to 

 this species. The segments are mostly shorter than the measurements 

 given by Kylin, and also shorter than the Alaska specimen quoted 

 above. The segment walls are also thinner. The material is young, 

 which may very probably account for the differences. 



The author is indebted to Professor W. A. Setchell for his critical 

 examination of this paper and for the Latin diagnoses. 



