“a 
324 Sketch of the Infusoria of the family Bacillaria. 
The small species (fig. 6) agrees pretty well with the above 
characters. It is common in ponds near West Point. I have also 
seen it in several American specimens of fossil infusoria. 
4. Gomphonema l. 3, fig.'7.) Frustules smooth, gemi- 
nate or in fan-shaped groups, one side elongated, wedge-shaped, trun- 
cate ; the other side obovate; pedicel repeatedly dichotomous. Marine. 
I have examined this species only in a dry state, having first 
noticed it on a glass slide on which I had preserved some speci- 
mens of Echinella flabellata from Stonington, Conn. 
The figure is drawn from the dry specimens. 
Ecurmetia, Ehr. 
Carapace simple, siliceous, fixed at one extremity to a pedicel, 
wedgeform, longer than broad, fan-shaped or verticillate by spon- 
taneous division. 
1. Echinella flabellata. (Pl. 3, fig. 8.) Smooth, corpuscles linear, 
cuneiform, truncate, slightly three-toothed, strize longitudinal, yo line 
without the pedicel. Licmophora flabellata, Ag. Greville in Hooker's 
English Flora, V, p. 408. 
his beautiful marine production presents in its fan-shaped 
sroups of crystal-like corpuscles, an exceedingly elegant appeat- 
ance. ‘The fans are supported by long flexible clavate pedicels, 
which are grouped together in large bunches covering filamentous 
marine Algz and zoophytes. : 
I found it quite abundant at Stonington, Conn. in July. Itissal 
to occur also at Scotland, Venice, and at the Cape of Good Hope. 
2. Echinella Pl. 3, fig. 9.) Corpuscles smooth? lanceo- 
late, truncate ; pedicel short, broadly clavate, often nearly circular, SUP- 
porting the radiating closely aggregated corpuscles. 
I detected this very elegant species about a year since in the 
Hudson River near West Point, where it grows upon Potamog? 
ton, Enteromorpha, &c. It agrees in many respects with E. ful- 
gens, Grev., but that is described as being striate, a character 
which I have not perceived on our species. 
~ Carapace simple, bivalve or multivalve, siliceous, fixed by né 
end, pediculate, lonzer than broad, pedicel in the direction of the 
axis of the body. (PedicellateNavicule.) 
nish them from Navicula, but the : 
CocconeMA. 
