1903] Collins,—— Notes on Algae,— VI 233 
The more one sees of Codio/um, the more difficult it is to draw sharp 
lines; forms can be found strikingly different from each other, but 
there are also many intermediate forms. The great need to clear up 
this matter is for some one to study them, in their natural conditions, 
through a whole season of growth: this might result in giving us reli- 
able distinctions, or might result in uniting all under one name or a 
few names. 
SPIROGYRA DECIMINA var. triplicata n. v. In a pool in the old 
slate quarry near Mystic Avenue, Somerville, Massachusetts, the 
writer found, May 20, 1902, a Spirogyra that does not agree exactly 
with any description accessible, but resembles .S. decimina (Müll.) 
Kütz. so much that it seems best for the present to consider it a 
variety only. The type has two spirals, but occasionally three; cells 
two to four times as long as the diameter, which is 35—40 m; spores 
broadly oval to subglobose. In the variety the spirals are uniformly 
three; the length of the cells varies from one and a quarter to 
five times the diameter, which is 40-45 um; the spores in the shorter 
cells are nearly globose, in the longer cells cylindrical with rounded 
ends. The variety has been distributed as No. 960, Phycotheca 
Boreali-Americana. ] 
In RHopnona, Vol. IV, p. 177, brief mention was made of the 
occurrence of ZYVectonema Battersii Gom. near Jonesport, Maine. It 
has since been found at Harpswell, Maine and Marblehead, Mass., 
and may naturally be expected anywhere along our northern coast, 
in the mixture of various minute Cyanophyceae which one so com- 
monly finds in tide pools and under overhanging cliffs. It is nearly 
related to P. Go/en&inzanum Gom., which occurs in similar localities, 
but the filaments are somewhat larger, 2—3.5 » in place of 1.2—2 p, 
and the trichomes are pale aeruginous in color instead of roseate. 
In both the trichomes are somewhat torulose, with articulations one 
third to one quarter their diameter. While Gomont's description ! 
represents the two as branching to the same extent, the American . 
specimens show fewer pseudo-branches in P. Golenkinianum than in 
P. Battersii. 
MICROCOLEUS TENERRIMUS Gomont, Monographie des Oscillariées, 
p.93, Pl. XIV, figs. 9-11. The cosmopolitan species M. chthono- 
plastes (Fl. Dan.) Thuret is very common in warm bays, lagoons and 
marshes, all along our coast; in the Gulf States and in California 
! Bull. Soc. Bot. de France, Vol. XLVI, pp. 35 & 36. 
