NEW BRITISH FRESH WATER ALGJ!. 
117 
Oocystis solitaria. Wittr. in Nord. et Wittr. Alg. Fxs. 224. West p- 
191. Toni Syll. Alg. p. 664. 
Cells for the most part solitary, 13-35x7-18 p, sometimes 
associated in families of 2 to 4 cells, ellipsoid ; membrane rather 
thick, with a small tubercle at each end. 
Clifden. 
Acanthococcus aciculiferus. Lager. Bidr. Sver. Alg. FI. t. 1 ,/. 21. 
West p. 191. 
Cells solitary, or collected in families, globose or subglobose, 
rarely oval, of variable size ; membrane of the cells thick, densely 
clothed with very numerous spines. 
Diam. without spines 20 p, with spines 26 p. 
Cromagloun. 
Acanthococcus sp. West Linn. Journ . 1892, 191, t. 18, /. 14. 
Cells solitary, or conglomerate in small families, globose ; mem- 
brane of the cells thick, furnished with numerous short, stout 
spines. 
Diam. without spines 34-42 p , spines 3-4 p. 
Burrew Hills, co. Clare. 
Botryococcus calcareus. West Linn. Journ. 1892, t. 18,/. 6. 
Thallus small, subglobose, of about 32 cells, free swimming, or 
aggregate in small masses; cells ovate, wedge-shaped, rather 
emarginate at the broader pole, with the narrow pole directed to the 
middle of the thallus. 
Size. Fam. 30-55 p diam. Cells 9-121 ^ l 0 ng 5 10-12- p 
broad, 7J-10 p thick. 
Amongst Spirogyra in small limestone pools. Burrew Hills, 
Co. Clare. 
Differs from B. Braunii in the very different shape of the cells, 
and in not having them so densely packed. 
Scenedesmus alternans. Beinsch. Alg. FI. 
Cells all equal, broadly elliptical to ovate-elliptical, rounded at 
the poles, twice as broad as long; families composed usually of 
eight cells, perfectly alternate. 
Lough Shannacloontippen ; near Oughterard ; near Recess ; 
Clifden ; Carrantuohill ; Adrigole. 
Scenedesmus denticulatus. Lagerh. Bidr. StocJch. Pedias, p. 61 t 2 
f. 13-16. West p. 193. Toni Syll. Alg. 564. 
Coenobium of four cells, ovate or ovate-oblong, cruciately dis- 
posed, or subalternate, rounded at each pole, and furnished mostly 
with two teeth ; membrane rather thick ; pyrenoid central 
7-8 x 5-11 p. 
Ballynahinch ; Lough Shannacloontippen. 
var. lineatus. West t. 18, f. 7. 
Cells oblong, narrower, and arranged in one series, not cruciate 
or alternate, with 2-3 small teeth. 
Cells 10-11 p long, 2§-4 p thick. 
Derryclare Lough. 
