CYTHERE. 
291 
shaped; valves smooth, glaucous, bright-orange. A very 
minute species. 
Hab. Berwick Bay. 
Cythere nigrescens, Baird.— Shell gibbously ovate, 
hinder end with a sharp point ; valves smooth, of a dirty- 
black colour. 
Hab. British coasts. 
Cythere minna, Baird. — Shell elongate-ovate, pointed 
behind ; valves white. The largest British species met with 
by Dr. Baird. 
Hab. Deep w r ater near Shetland, where it w f as dredged 
by Mr. M‘Andrew r . 
Cythere inopinata, Baird. — Shell oblong, ovate, white, 
with a slight orange-coloured mark on upper edge ; each 
valve with a gibbous projection about the middle. 
Hab. Small pond between Hanw 7 ell and Southall, Mid- 
dlesex. Dr. Baird called this “ inopinata ” — unexpected— 
from its curious habitat , it being the second species only re- 
corded as inhabiting fresh-w T ater. It is a very small species, 
and always creeps at the bottom. 
Cythere angustata, Munster, sp. — Shell oval-oblong, 
pale yellow-surface -polished ; when seen under the micro- 
scope it is covered with small asperities. 
