SOME DESMIDS OF THE UNITED STATES. 317 
148. SravrastRUM VESTITUM, Ralfs, Brit. Desm. p. 143, t. 23. 
f. 1. 
Var. TORTUM, n. var. (Pl. 18. fig. 16.) 
Var. semicellulis a vertice visis processibus curvatis (ut in 
S. cyrtocero) et tortis. 
Lat. 65 u. 
Hab. Bridgeport, Conn. 
The processes are not only curved but twisted on their axes, 
the dorsal verruce causing the outer curve of the processes to be 
very rough and the inner one almost smooth. 
149. S. GRACILE, Ralfs, 1845; Brit. Desm. p. 196, t. 22. f. 12. 
A figure is given (Pl. 18. fig. 7) of an abnormal form from 
Whitmore Lake, Mich. (H. J. no. 456). 
150. S. concinnum, n. sp. (Pl. 18. fig. 17.)— S. forfieulatum, 
Wolle, Desm. U. S. p. 144, pl. 51. ff. 16-19 (non Lundell). 
S. submagnum, 12-plo latius quam longum (cum processibus), 
modice constrictum, sinu aperto acutangulo; semicellule sub- 
trapeziformes (vel obverse semicirculares), angulis in processus 
horizontales breves validos produetis, marginibus processuum 
spinulosis, apieibus processuum cum spinis magnis divergen- 
tibus tribus, dorso leviter eonvexis cum processibus brevibus 
bifurcatis 6 ad marginem; a vertice vise triangulares vel 
quadrangulares, angulis in processus breves productis, lateribus 
concavis cum processibus brevibus bifurcatis 6 ad marginem 
Unumquemque. 
Long. 44 u; lat. 68 p; lat. isthm. 14 p. 
Hab. Florida (H. J. no. 555). 
This is evidently the same plant as the one Wolle named 
8. forficulatum. Johnson remarks that the short bifurcate 
Processes are sometimes twice bifid. It seems to us to be nearer 
8. vestitum, Ralfs, than S. forficulatum, Lund. 
151. 8. ELONGATUM, Barker, in Quart. Journ. Micr. Sc. ix. 
p. 424.— S, terebrans, Nordst. 
Long. 65 H; lat. 36-42 u; lat. isthm. 9 p. 
Hab. De Land, Florida; common. 
n S. LEPTOCLADUM, JVordst. in Vidensk. Medd. Naturh. 
oren. Kjóbenh. 1869, nos. 14-15, p. 228, t. 4. f. 97. Inclus. 
var, cornutum, Wille, in Bih. till K. Sv. Vet.- Akad. Handl. 
TH. no. 18, t. 1. f, 39. 
LINN, — . 
JOURN.— BOTANY, VOL. XXXIIL 2^ 
