86 
Edwards, on Diatomacecs. 
ATLA.NTIC COAST. 
On algse collected at different points along the coast, from 
Boston to New York, were found — 
Achnanthes longipes. Podosira Iiormoides. 
Biddulphia pulcliella „ Montagnei. 
Cocconeis scutellum. Rhabdonema adriaticum. 
Grammatophora marina. Striatella unipunctata. 
„ subtilissima. Sjnedra radians. 
Melosira nummuloides. „ undulata. 
Podocystis americana. 
GLEN-COYE SHORE. 
Growing attached to Zostera marina, in the Bay of Glen- 
cove, Long Island, at the mouth of a fresh-water creek, and 
about thirty miles from New York City, were found — 
Achnanthes longipes. Epithemia musculus. 
Actiuocyclus undulatus. Grammatophora marina. 
Amphora affinis. Melosira nummuloides. 
Cocconeis scutellum. Navicula didyma. 
Coscinodiscus eccentricus. Nitzschia birostrata. 
oculus-iridis. Stauroneis pulchella. 
GREENPORT, L. 1. 
Attached to and growing on algae at Greenport, in Peconic 
Bay, Long Island, were found — 
Achnanthes longipes. Navicula ovalis. 
Actinocyclus undulatus. „ lyra. 
Biddulphia pulchella. Orthosira marina. 
Coscinodiscus eccentricus. Podocystis Americana. 
Cocconeis scutellum. Podosira hormoides. 
Epithemia musculus. Pleurosigma strigilis. 
Grammatophora subtilis. Synedra fulgens. 
Rhabdonema arcuatum. „ radians. 
Striatella unipunctata , „ undulata. 
In this gathering was found a form which I take to be a 
Podosphceniaj but which agrees with none of the described 
species. On F.V. it resembles the other species, but the 
valve is somewhat of the form of the F.V. of Rhipidophora 
paradooca, only somewhat more acute at the lower extremity. 
It has a median line, and is traversed by extremely fine 
strise, but is destitute of the so-called vittce found in Podo- 
sphcenia. It was found growing attached to algae, without a 
stipes. 
BAY OP PUNDY. 
In the mud washed from dredgings taken in ten to twenty 
fathoms off Eastport, Maine, in the Bay of Fundy, by W. 
Cooper, Esq., were found — 
