SOME DESMIDS OF THE UNITED STATES. 295 
A form with an extra basal tooth; lat. 60 p; cfr. West in 
Journ. Linn. Soc., Bot. xxix. p. 133, t. 20. f. 9. 
Hab. Seattle, Wash. 
59. MicnasTERIAS FURCATA, Ralfs, Brit. Desm. p. 73, t. 9. 
f. 2 (1848).—M. pseudofurcata, Wolle, 1881; Desm. U. S. p. 111, 
t. 35. f. 4.—M. furcata var. decurta, W. B. Turn. in Journ. Roy. 
Mier. Soc. 1885, p. 936, t. 16. f. 10.—M. furcata var. simplex, 
Wolle, 1885; Aly. U. S. p. 40, t. 59. ff. 6-7. 
Hab. DeLand, Florida. “ Found it abundant in material 
collected in 1895. All forms were present, from typical oues to 
those with the lateral arms undivided. A specimen showing 
one-half of the * pseudofurcata’ ty pe and the other half of the 
simplest is preserved in H. J. no. 560. Diam. of simplest part 
196 u, of other 144 u.” (Fig. xylogr. 2b.) 
O 
<, 
— 
Y 
Fig. 2—~Micrasterias furcata, Ralfs. a et b, x 340. 
