446 TRANS. OF THE ACAD. OF SCIENCE. 
tion to the structural development manifested in the species 
described below. A mere difference in the mode of growth 
= —_—~? be deemed sufficient for generic distinction. The 
rm, arrangement, and general character of the cells, to- 
pa with differences in other anatomical relations, should 
form the only true basis of classification. In its general char- 
acters, it is allied in structure to Semicoscinium. 
LrmaRIA FALCATA, n. sp. 
Bryozoum a flattened pepennion: cell-sheaths solid, long, 
forked, with triangular imbricating apertures filled partl 
with remains of small cells; about b Be plates oe cue 
the cell sheaths being in ‘the lower ones _nearl obsolete ; 
comparison _ us, we will assign to it the provi 
e 
Geol. Pos. and <e —Devonian, Falls of the Ohio. In Dr. 
B. F. Shumard’s collection. 
9x12 
=“ | FLUSTRA SPATULATA, 0. Sp. 
Bryozoum, a double leaf-like calcareous expansion formed 
of spatulate cells truncated at their prose = extremities 
more or less quincuncially, or alternately arran, 
Fak ss 
fongitudinal y, and in rt rows eee a 
_Tows twen = cells transversely; cells a ders over or 
f a line lon; » and « one-sixth wide” 
es 
our ] 
an foowals es i ieee 
of Sussex,) but t4a 4. 
cells, by the divisional iy te 
ener covering of the cell chambers. 
