296 W. AND G. S. WEST 



CHROOCOCCACE^E 

 Genus ASTEBOCYSTIS Gobi 



74 Asterocystis antarctica sp. n. (PI. XXVI, Figs. 103-106) 



A. minuta, inter varias algas libere natantes ; filis brevibus, vaginatis, vix ramosis, 

 valde contortis, e serie singula cellularum formatis ; vaginis arctis, achrois et 

 gelatinosis; cellulis ante divisionem ellipsoideis, post divisionem subhemisphsericis 

 vel elongato-hemisphsericis, tarn longis quam latis vel brevioribus ; cytioplasmate 

 a3rugineo et granuloso (verisimiliter ut in Chroococco minuto). 



Long. cell. 4.5-8 M ; lat. 6-8 /" ; crass vag. 9-10 /". 



Hob. Green Lake. 



Asterocystis antarctica is of about the same size asA.africana G. S. West (inJourn. 

 Linn. Soc, bot. xxxviii, 1907, p. 196), but is of a different habit and has cells of a 

 different form. The short, contorted filaments, almost without any trace of branches, 

 distinguish it at once from all the other species of the genus. 



Genus MICROCYSTIS Kiitz. 

 75 Microcystis chroococcoidea sp. n. (PL XXVI, Figs. 107-114) 



M. coloniis parvis, libere natantibus, e cellulis paucis (6-24) compositis, tegumento 

 gelatinoso et achroo, vix conspicuo ; cellulis confertis sed irregulariter aggregatis, iis 

 periphericis interdum paullo minoribus, contentu pallide flavo-a3ruginoso, subtiliter 

 granuloso cum granulis conspicuis majoribus 2-4. 



Diam. cell. 4-7 /" ; diam. colon. 14-33 n. 



Hob. Green Lake. 



This member of the Chroococcacese was not uncommon in the strongly saline 

 water of Green Lake. The colonies are very small, free-floating, and often do not 

 consist of more than a dozen cells. The cells are closely aggregated to form a some- 

 what irregular colony, in which the peripheral cells are sometimes slightly smaller 

 than the others. The cells do not possess an independent envelope, but are all enclosed 

 in a very thin and almost invisible mucous integument. The alga forms a connecting 

 link between the genera Microcystis and Chroococcus, and might equally well be 

 named " Chroococcus microcystoidea," 



Genus GLCEOCAPSA Kiitz. 

 76 Glosocapsa. shuttleworthiana Kiitz. 



Phyc. gener. 1843, p. 175 ; Tab. Phycol. I, p. 18, t. 23, f. 1 ; Forti, Syll. 

 Myxophy. 1907, p. 37. 



Diam. cell. 2.5-3.5 n, c. integ. prim. 7-8 M ; tegumentis internis intense aurantio-rubris. 



Hob. On stones, High Moraines, Mt. Erebus. Also fragmentary in pond, Cape 

 Royds. 



