new Species of Marine Shells. 119 
of the basal margin. From Arca (Nucula) minùta of 
British authors, it is distinguished by the absence of im- 
pressed stris. In its general outline it is shaped not 
unlike a boat, or perhaps a half-moon. Only a single 
valve was found of the size here indicated ; but half a 
dozen perfect specimens have been obtained, measuring 
from five to seven-twentieths of an inch in length. I 
am indebted for them to the kindness of William W. 
Wheildon, Esq. of Charlestown, by whom they were 
taken from the stomach of cod, a off Mes in 
the month of July. 
BurLA LINEOLATA. 
Plate Ill. fig. 15. 
testA parvulá, oblongo-ovatá, ferrugineá, transversim obliqué fre- - 
BAE ES striatA, spirà prominulA, apertura magni, ad basim valdà 
dilatatà et sub-effusa. 
Description. Shell small, oblong-ovate, broadest 
at the base, color a pale brown, covered with a thin, 
ferruginous epidermis, and markéd with numerous im- 
pressed, oblique, transverse striz, composed of three vo- 
lutions, the last enveloping all the rest; spire slightly | 
prominent, lip arising from near its summit ; aperture 
extending the whole length of the shell, narrow supe- 
riorly, and very much dilated towards the lower ex- 
tremity ; somewhat effuse at the base ;- near the middle 
of the columella is a very faint oblique fold. Internal 
color a glossy yellowish white. 
Lensth six-fortieths, breadth three-fortieths of an inch. 
 Inhabits the waters of Massachusetts Bay. 
In the collection of the Bost. Soc. of Nat. History. 
