1898] SOME WEST AMERICAN THERMAL ALG 103 
47.5°C. Near Upper Geyser Basin, Yellowstone National Park. 
[E22 TE 1806. 
SprruLINA Major (Kg.) Phyc. Gener. 183. 1843. Tilden, 
Am. Alg. Cent, II. no. 193. 1896. (Pl. VILL, fig. 19.) 
Forming a thin brittle scurfy scum, whitish on top ; stratum 
dull green (prasinus); trichomes pale green, wound into some- 
what straight, dense, very regular spirals with a diameter equal- 
ing 3u, in thickness Im; turns contiguous. 
(2) On surface of still pool into which overflow runs. Tem- 
perature 41°C. Mammoth Hot Springs, Yellowstone National 
mike 3-1. 8 jl 1806, 
(6) Overflow of channel of geyser. Temperature 49-54.5 C. 
Spasmodic Geyser, Upper Geyser Basin, Yellowstone National 
Park. W.H.W. 1897 
(c) Forming a whitish brittle scum in the hot water. Beck’s 
Hot Springs. Salt Lake City, Utah. J. i. 1. 7 Ji 4897; 
_ This Species is quite common in both the calcareous and 
siliceous waters of the Park. It is generally found with other 
alge. I did not find any pure growths. 
Spirulina caldaria, n. sp. (P2. VIII, fig. 20.) 
f Stratum widely expanded, dark aeruginous ; trichomes aeru- 
Sinous, short, somewhat straight and stiff, forming a very lax 
Spiral with a diameter of 1.5m, O.gm in thickness ; turns 3.24 dis- 
tant from each other. 
ae Forming thick richly colored strata on surface of hot 
A very near outlet of the springs. Natural Sulphur Springs, 
nit, Canada. J.E.T. 13 Ag 1897. 
pxEcHococcus @®RuGINosuS Neg. Einz. Alg. 56. 1849. 
Go Am. Alg. Cent. II. no. 195. 1896. Described in Bort. 
"24° 198. pl. 8. fig. 6. S. 1897. 
ee eocaPA VIOLACEA (Corda) Rabenh. Fl. Eur. Algar. 2+ 41- 
re Tilden. Am. Alg. Cent. II. no. 196. 1896. Described in 
= A8+ 108. O. 8. fig. 5. S$. 1897. 
