21,1 Shaw: Merrillosphaera 123 
MERRILLOSPHAERA AFRICANA (West) comb. nov. 
Volvox africanus West in Journ. Quekett Mic. Club II 11 (1910) 
102-108, pl. 3, figs. 8-10; and II 13 (1918) 425-428, pl. 29, figs. 4-6. 
Coenobia ovoid; ranging from 295 by 345 » to 480 by 610 xz. 
Number of somatic cells between 3,000 and 8,000. Somatic 
protoplasts almost globose, 8 to 9.5 » in diameter; about 25 x» 
apart at anterior pole, and grading to much smaller distances 
at posterior pole. Gonidia 1 to 4; arranged more or less in 
pairs; gonidium or pair of gonidia near posterior pole smaller 
than the others and producing smaller daughters. Gonidia of 
the daughters in some cases divide and produce granddaughters 
containing gonidia that are the beginning of the fourth genera- 
tion while the daughters are still within their mother. Daughter 
coenobia strongly ovoid and more or less flattened by mutual 
pressure; granddaughters spherical. Female coenobia with 70 
to 80 oospores (average 74) ; oospores with thick smooth walls, 
average diameter 45 ». Description of male coenobium not yet 
published. 
Habitat.—Albert Nyanza, Africa (leg. R. T. Leiper, 1907) ; 
Ussangu Desert, German East Africa (leg. A. W. Jakubski, 
1909-10) ; fresh-water pools near Manila, Philippine Islands 
(leg. W. R. Shaw, 1914). . 
LITERATURE CITED 
Carter, H. J. (59). On fecundation in the two Volvoces, and their specific 
differences. Ann. & Mag. Nat. Hist. III 3 (1859) 1-20, pl. 1. 
EHRENBERG, C. G. (’38). Die Infusionsthiere als vollkommene Organis- 
men. Berlin and Leipzig (1838). (Not seen.) ee 
Harper, R. A. (’18). Binary fission and surface tension in the develop- 
ment of the colony in Volvox. Brooklyn Bot. Gar. Mem. 1 (1918) 
154-166, pl. 2 and figs. 1-4. 
JANET, C. (712). Le Volvox. Limoges (1912) 151 pp. | ; 
KLEIN, L. (’89A). Morphologische und biologische Studien iiber die Gat- 
tung Volvox. Jahrb. f. wiss. Bot. 20 (1889) 183-211, pls. 10-12. 
KLEIN, L. (’89B). Neue Beitrage zur Kenntniss der Gattung Volvox. 
Ber. d. deutschen bot. Ges. 7 (1889) 42-53, pl. 3. fei 
KieIn, L. (90). Vergl. Untersuchungen tiber Morphologie und Biologie 
der Fortpflanzung bei der Gattung Volvox. Ber. d. naturf. Ges. 
Freiburg i. B. 5 (1890) 92 pp., pls. 2-6. 
Meyer, A. (96). Die Plasmaverbindung und die Membranen von Volvox, 
mit Riicksicht auf die thierischen Zellen. Bot. Zeit. 54+ (1896) 187- 
217, pl. 8. : “is 
Powers, J. H. (07). New forms of Volvox. Trans, Am. Microscop. 5 
27 (1907) 123-149, pls. 11-14. 
