SMITH: ALGAE FROM THE LAKES OF WISCONSIN 475 
Reproduction, aside from cell division, unknown. (Name from 
Gloeocystis and 81s, appearance.) 
This genus combines the general external morphological char- 
acteristics of Gloeocystis Naegeli and the cell shape of Nephro- 
cytitum Naegeli. Although ovoid cells have been described in 
species of Gloeocystis, the cells of this species are too markedly 
lunate to be classed with Gloeocystis. The enveloping mucilagin- 
ous mass around the cell aggregates is not lamellated as in Gloeo- 
cystis, neither is there a common gelatinous envelope for these 
aggregates. On the other hand although the cell-shape resembles 
certain Nephrocytium species (N. allantoideum Bohl. for example) 
the ovoid colonies of Nephrocytium are not composed of distinct 
aggregates of cells, each with its own envelope. 
A further study of the method of reproduction, whether by 
autospores or zoospores, will determine the exact systematic 
position of the genus. From the data at hand the natural in- 
ference is that it should be placed in the vicinity of Gloeocystis. 
Gloeocystopsis limneticus sp. nov. 
Cells 15-104 long, 6-4 wide. Cell aggregates 30-254 in 
diameter. Colonies up to 125 u in diameter. 
PLATE 24, FIG. 12 
DIstRIBUTION: plankton, Catfish and Harris Lakes. 
The alga was found in two lakes in northern Wisconsin which are 
about fifty miles apart and on different watersheds. The di- 
mensions of the alga are the same in both stations. It is probable 
that Gloeocystis Rehmanni Woloszynska from Africa is another 
species, but since the original description is very vague and no cell- 
dimensions are given, it must remain a doubtful species until 
more fully described. 
Pediastrum sculptatum sp. nov. 
Colonies oval or circular discs of eight to thirty-two cells. In- 
terior cells four- to six-sided with few interstices between the cells. 
Marginal cells bilobed, with the lobes produced into divergent or 
Parallel horn-like processes. Cell wall covered with a network of 
very fine ridges. 
Diameter of colonies 150-80 y; diameter of cells 15-10 y. 
