1919] Sctchell-Gardner : Myxophyceae 99 



7. Calothrix epiphytica AV. and G. S. West 



Filaments epipliytic upon larger algae, solitary or aggregated 

 into small clusters, attached at the base and erect, or procumbent, 

 5-7. 5u diam., 250/i,, rarely 350/.1, long, gradually attenuated from the 

 base to the apex, not branched; sheath transparent and colorless, 

 inconspicuous; trichomes aeruginous, 3.5-4/a diam. at the base, taper- 

 ing gradually into a delicate hair at the apex ; cells quadrate, slightly 

 longer above and shorter below, heterocysts small, solitary, basal. 



Growing on Ehizoclmviwni riparmm var, polyrhizum Rosenv., on 

 sand rock along high-tide level. Near the mouth of Tomales Bay, 

 Marin County, California. August, 1910. No. 3440, Gardner. Dis- 

 tributed in Collins, Holden, and Setchell, Phyc. Bor.-Amer. (Exsicc), 

 no. 2238(7, on the above mentioned host. 



West, W., and G. S., Welwitsch's African Alg., 1897, p. 240. 



The type was found growing on Oedogonmm sp. on the bank of 

 the River Bero at Massamodes, Africa, August, 1859, no. 190, Wel- 

 witsch. 



This is the first and only locality on our coast from which this 

 species of Calothrix has been reported. The material is mixed with 

 Lynghya Willei S. and G. and is not very abundant. It seems strange 

 to fiiid a fresh water species on the edge of an ocean and it may be 

 that our plant is different from that of the Wests. The agreement 

 seems too close, however, to refer it elsewhere, but the material is not 

 sufficiently abundant to make the determination thoroughly satis- 

 factory. 



8. Calothrix Crustacea Thuret 



Filaments caespitose, or velvety and widely expanded, dark green 

 or brownish, erect, straight, dense, 1-2 mm. high, 12-20/^ even up to 

 40/x diam., thickened at tlie base; sheaths somewhat thick, hj^aline or 

 yellowish brown, mostly lamellate, ocreate; trichomes olive green, 

 8-15/x, diam., prolonged above into a very delicate acute hair; cells 

 short, heterocy.sts 1-3, basal and intercalary ; hormogonia numerous in 

 a sheath, 4-5 times as long as the diameter; "spores seriate, o])long- 

 cylindrical, smooth." 



Attached to sticks, weeds, and stones in salt marshes, in the upper 

 littoral belt. Washington to California. 



Thuret, Notes Algol. I, 1878, pp. 13-16, pi. 4 (figures 5, 6 drawn 

 from living material collected at Croisic) ; Setchell and Gardner, Alg. 



