On some species of Micrasterias. 
L. N. JOHNSON. 
WITH PLATE VI. ; 
The genus which forms the subject of these notes includes 
some of the largest and most beautiful of the Desai 
During the past summer the writer has had an opportunity ot 
studying an abundance of material of a number of ape rs. 
cluding one or two rare forms. Some of the facts note ; 
not appear to have been previously recorded, though aa 
ently of considerable importance. Most of the mate aa | 
collected on Long Island, in several large ponds, at Lol | 
Spring Harbor. : Jian 
Probably the most interesting find was Micrastertas fo és 
cea Bailey. This was very abundant in one gathering ey 
by rinsing waterweeds. The species was first describe 6d 
Prof. Bailey, in 1847, in a letter to Ralfs, and was publis a 
and figured by the latter in his British Desmidiez. = It 1s 
parently not a common species, though widely distribut : 
It has been reported from Burmah by Joshua, ”? from vue 
by Wallich,* from Java by Nordstedt. In this country ee 
found it once or twice,* but no one else appears to wp . 
ported it since Bailey’s original discovery. Prof. No a 
has described® a variety ornata, from Brazil, differing | te: 
the type only in having, on the superior margin of the Ye 
mediate lobe and the inferior of the basal lobe, two S™® 
aculei. . 
to 
were counted in a single filament, and the number apps 
be limited only by the strength of the connection of the the 
and the strain put upon it. Wallich appears to have been UE 
RIA RENAE Paes peter 
tThe British Desmidiezx, 210. 
2B 
a plo oe fF) a 1848. 
urmese Desmidiez, Journal of the Linnean Soc. 21: 636. 886. ist 
oi ee of Desmidieze from lower Bengal. Ann. and Mag. ote 
. 6: 280. pl. rg. f. 7-9. : tes: 
‘Bulletin of Torrey Hetasseel Club 9: 27. 1882. Desmids of the United S14 
118. pl. 78. f. 10, 11. 1884. toula quint 
*Symbolz ad floram Brazilie centralis cognoscendam. _Particula 22i. pl 
Carag Vidensk. Medd. fra den naturh. Forening i Kjébenhavet 
2 . 1869, 
