118 



OOCYSTIS AND ERKMOSPHiERA, 



Syn., 0. elliptica W. West, Alg. Eng. Lake Distr., 1892, p.24, 

 f.56; and f. minor W. West, I.e., and New Brit. Frw. Alg., 1894, 

 p.U, f.26; W. & G. S. West, Frw. Alg. Madagascar, 1895, p.82, 

 P1.5, f.l3, 14. 0. rupestris Kirchner, Alg. von Wiirttemberg, 

 1880, p.l69, T. ii., f.2. 0. pelagica Lemm., Ber. z. Kenntn. d. 

 Planktonalg., xiv., 1901, p.95, T. iv., f.7; also Nord. Plankt., 

 xxi., p. 17, f.56. 



It is always unsatisfactoiy to have to pass over a well-defined 

 specific name for one which is obscure, but I feel bound to agree 

 with Chodat, Alg. vertes, p. 189, that 0. elliptica W. West, is 

 identical with 0. Ndgelii A.Br, The one character given by the 

 latter in his description, ^'ceflulis oblonr/is," is fortunately decisive. 

 It indicates a form longer than broad, with broadly rounded, or 



Text-fig. 7. Text-fig. 8. 



Oocystifi elliptica W. West, Oocy.MiH rupestris Kirchner; 



( X 520); after West. after Kirchner. 



rounded subtruncate, ends and very slightly arcuate sides. 

 West's description of 0. elliptica, I.e., agrees perfectly with this, 



^'cellulis ohlonyo-ellipticis, apicibus rotundatis et non in- 



crassatis." 0. rupestris Kirchn., has been placed by Hansgirg as 

 a variety, and by other authors as a synonym, of 0. solitaria 

 Wittrock. The latter, however, is narrowly elliptic, with ends 

 acutely rounded and inwardly incrassate, whereas Kii'chner, I.e., 

 says of 0. rupestris, ''Zellen oblong," and though his Fig.2« is 

 somewhat irregular, it is certainly intended to have broadly 

 rounded ends and slightly arcuate sides. The other figures 

 merely serve to show the character of the mother-cell and the 

 disposition of the autospores. 



The only other oblong form that I know of, is (fide W. West, 

 New Brit. Frw. Alg., PI. ii., f.28) 0. yiyas Archer, which is out 



