BY G. 1. PLAYFAIR. 141 



OocYSTis sociALis Osteufeld. 



Cells 4-8 in a family, elliptical, 15-20/x long and 8-1 2 // broad, 

 with two chloroplasts. 



Cf. Ostenfeld, Phytopl. fiu det Kasp. Hav., (Medd. fra den 

 naturh. Foren. Kopenhagen, 1901) p. 138, f. 10. I have not seen 

 this memoir, and the details I give ai-e from Lemmermann, Nord. 

 Plankt., xxi., p. 16. 



Synonyyns. 



0. rupestris Kirchner=0. JVdgelii A. Braun. — " Zellen ob- 

 long, ungefahr doppelt so lang als dick, meist einzeln, da die 

 Mutterzellhaut sehr friih zerrissen wird." Kirchner, I.e. 



0. setigera Archer = Lagerheimia spec. — Quart. Journ. Micr. 

 8ci., 1877, p. 194, M. C. Cooke, Brit. Frw. Algte, p. 27, remarks: 

 "We are unable to give any description of this species, which, so 

 far as we ai-e aware, bears only a manuscript name." 



0. ciliata Lagerheim = Lagerheimia ciliata (Lag.) Chodat. — Cf. 

 Lagerheim, Pedi. Protococc.o. Palmell.,(K.Vet.-Akad.Forh., 1882, 

 No.2)p.76,T.iii.,f.33-37. Syn., Chodatella c-i^ia/!«(Lag.). Lemm.* 



0. ciliata (3 amphitricha Lag. = Lagerheimia ciliata var. amphi- 

 tricha. Cf. Lagerheim, Bidr. t. Sveriges Algflora, (K. Vet.-Akad. 

 Forh., 1883, No.2) p.61, T. i., f.25, 26. 



0. ciliata var. radians W. & G. S. West = Lagerheimia ciliata 

 var. amphitricha Lag. Cf. W. it G. S. West, New and Inter- 

 esting Frw. Algs-, J.R.M.8., 1896, p.l61, PI. iii., f.l5. 



0. Echidna Bohlin = Lagerheimia Echidna (Bohlin). Cf. 

 Bohlin, Zur Morph. u. Biol, einzell. Alg., p.518. Syn., Chodatella 

 Echidna (Bohlin) Chodat, Alg. vertes, p. 192. 



0. Ndgelii, forma, Nord. = 0. Nordstedtiana (De Toni) mihi. 



0. Ndgelii f. Nordstedtiana Le Toni = 0. Nordstedtiana (De 

 Toni) mihi. 



0. rotunda Schmidle=0. Nordstedtiana var. rotunda (8chm.) 

 mihi. 



* In Plankton of the Sydney Water-Supply, the.se Proceedings, 1912, 

 Vol. xxxvii., Part 3, I have shown that Lagerheimia and Chodatella are 

 one. There is no generic diiference in the set;e, which are interchangeable 

 in the same form. 



