oe Veal Mee 
VOLUME XXxIlI NUMBER 5 
bORANICAIL (GAZETTE 
NOVEMBER, roor 
NEW OR LITTLE KNOWN UNICELLULAR ALGAE, 
{l.— EREMOSPHAERA VIRIDIS AND EXCENTROSPHAERA. 
GEORGE THOMAS MOORE, 
(WITH PLATES X—XI!) 
Eremosphaera viridis. 
Amonc the many algae which have been supposed to rep- 
resent stages in the life history of other plants, perhaps none 
have had such a variety of positions ascribed to it as the beau- 
tiful spherical form known as Evemosphaera viridis. This species 
was described by De Bary in 1858 in his Untersuchungen iiber die 
Familie der Conjugaten as a desmid, although he had not observed 
anything resembling conjugation in the plant, and could only 
determine its affinities by the mode of division and its general 
Similarity to other well known desmid forms. About the same 
time, Henfrey (5) found this unicellular organism in bogs in 
Northumberland, and described it as Chlorosphaera Oliveri. A 
Sood account of the general structure of the plant is given, and 
because of certain appearances which he assumed to be anthe- 
ridia, Henfrey says ‘in the vicinity of Oedogonieae they (Chlo- 
rosphaera) will find their true place.” Hofmeister (6), who 
described Eremosphaera in his memoir on the Desmidiaceae and 
Diatomaceae, without giving it a name, regarded it as a link 
between the Desmidiaceae and Palmelleae. 
Twenty-five years later De Wildeman in a measure con- 
firmed the view of De Bary, but stated that Eremosphaera 
309 
