128 METROPOLITAN PARK FLORA. 
HAPALOSIPHON, Naeg. 
H. pumilus (Kuetz.), Kirchner. 
M, on under side of Nuphar leaves, Spot Pond and Shiner 
Pool. 
STIGONEMA, Ag. 
S. hormoides (Kuetz.), Born. & Flah. 
M, in gelatinous masses on rocks, Cascade. 
S. panniforme (Kuetz.), Born. & Flah. 
M, wet rock. 
S. mamillosum, Ag. 
M, Cascade; on pebbles at margin of Spot Pond. 
HASSALLIA, Berk. 
H. byssoidea (Berk.), Hassall. 
M, among other algz, Cascade. 
TOLYPOTHRIX, Kuetz. 
T. tenuis, Kuetz. 
M, on mosses and various small plants, Spot Pond. 
NOSTOC, Vauch. 
N. sphzricum, Vauch. 
M, minute blackish or greenish rounded masses on wet rocks, 
Cascade. 
ANABAENA, Bory. 
A. catenula (Kuetz.), Born. & Flah. 
M, on dead leaves, etc., in swamp near Bear’s Den path. 
A. oscillarioides, Bory. 
M, with the preceding species. 
CONJUGATE. 
ZYGNEMA, Kuetz. 
Z. cruciatum (Vauch.), Ag. 
M, in pond. 

