LL St 
Ea ee a ee 
St at Ly ee ee a rr a ee eee AP 
ON SOME ALG FROM HOT SPRINGS 245 
15. Phormidium oe ae (as:) Gomont. Crass. trich. 1:3- 
16». Hveravellir, temp. C. This species occurs frequently 
on stones and rocks in warm spe 
16. Phormidium angustissimum West & G. 8. West in Journ. 
Bot. 187, p. 298. Crass. trich. 0°7 ». Hyveravellir, in hot spring, 
temp. 55° C. Also in spray of a small geyser, temp. o ok spray 85 rie 
In the stream from the Great Geyser, mean temp. a 
Gomont has recently described a species of this Fonts under the 
name of P, Treleasei (cfr. Bull. Soe c. Bot. France, 1899, tom. xlvi. 
17, Phormidium tenue (Menegh.) Gomont. Crass. trich. 1-8- 
2p; Rue cell. 8°5-4'8 ». Hyeravellir, in spray of small geyser, 
temp. 85° C, 
18, oe subuliforme Gomont. Crass. trich. 2°6-2°9 p 
long. cell. 4°7-7-4 ». Apices of trichomes sat a slightly 
curved ; apical cell stictewelent acutely conical; ce tents very 
evanulose. Hveravellir, temp. 55° C. This species se only pre- 
viously been observed in the island of St. Paul, in the Pacific. 
19. Oscillatoria limosa Kiitz. Crass. trich. 18 ». Hveravellir, 
temp. 49° O. 
20. Oscillatoria proboscidea Gomont. Var. trichomatibus paullo 
crassioribus; cellulis diametro 24-3-plo brevioribus, levissime tu- 
midulis. Crass. trich. 15°3-18 »; long. cell. 5-5-7°7 ». Hveravellir, 
in hot spr ings, temp. 24°-38° C. In stream from Great Geyser, 
-80 
are a little ti oka: ‘and the cells are “oft n very anatase swollen. 
i le; some were obtusely 
ic 
O. trapezica Tilden (in Bull. Torr. Bot Club, Feb. 1896, vol. cil, 
No, 2, pp. 58- um fig. xylogr.), some of the cells being wider 
than others, and the apical cell yi merely rounded. ? 
21. Oscillatoria numidica ings Crass. oe 3°6-4 
siream from Great Geyser, mean temp. about 40° C. This species 
as only previously coe hears from hot springs at Hammam 
Salahin, Numidia. 
22, Plcscoed helveticus Nig. Diam. cell. ‘7-85 p, Ari 
integ. 11-5-14-5 p, Hveravellir, on rocks and stones among Catlo- 
thrie parietina vay. thermalis, temp. 24° C. 
BaciLLaRIEz. A ae 
F ec. Amphora Normanii Rabenh. Hveravellir, temp. 49° an 
0. 
4. Navicula viridis Kiitz. Hveravellir, temp. 38° and 60° 
In sue of small geyser, temp. 85° C. In stream from Great 
