THE LIFE HISTORY OF GLOEOTAENIUM 
EDGAR N. TRANSEAU 
(WITH PLATE III) 
This peculiar alga was first collected by LOITLESBERGER at 
Ischl, Austria. On the basis of that material, Hanscirc in 1890 
described the genus and only known species, naming it for the 
collector, Gloeotaenium Loitlesbergerianum (1). He characterized 
the 2 and 4-celled families, with their encircling black bands. The 
chromatophore was stated to be star-shaped with a large central 
pyrenoid, and reproduction was limited to the multiplication by 
separation into two families. He thought the alga to be related to 
the desmids, and placed it together with S pirotaenia in a new family, 
the Pseudodesmidiaceae, which he conceived to be intermediate 
between the Desmidiaceae and the Palmellaceae. 
In 1891 STOCKMAYER published a more detailed account (2) of 
the structure and life history, also based on a part of the material 
collected by LorrtesBeRGER. He figures the 2 and 4-celled 
families and what he took to be a 1-celled individual. His 1-celled 
form, however, was either a diseased specimen or some other alga. 
The black band is described as originating by the gelatinization of 
the next to the outer layer of the mother cell wall in the plane of 
division. As gelatinization proceeds, the band is pushed inward 
until it occupies a position between the daughter cells. This pro- 
cess is preceded by the cell division and takes place about the same 
time that the outer gelatinous wall of the mother cell disappears. 
Gelatinous ‘“‘caps” then develop near the poles of the mother cell, 
and as the second division takes place, these caps elongate in the 
plane of the second division until they fuse with the black band 
already formed. Inasmuch as polar “caps” also appeared in the 
4-celled families, the author suggested the possibility of 8-celled 
families. 
STOCKMAYER made it evident that the plant is not at all related 
to the Desmidiaceae, and that the black bands are hardly of sufli- 
cient importance to warrant the making of a new family. He con- 
Botanical Gazette, vol. 55] [66 
