54 
CALIFORNIA SEA SHELLS. 
as its name indicates. It would be impossible 
to give a figure which would illustrate all its 
phases, for it is exceedingly variable. Normally-, 
it is an oval little shell, with regular sculpturing. 
But it has a habit of getting into a hole in the 
recks and growing to fit the premises ; so it fre- 
quently is much distorted, generally growing 
long and narrow. The ligament is external ; the 
hinge teeth often become nearly obsolete, as well 
as the sculpturing, and the shell becomes thick 
and rough. Color, white; breadth, from one- 
half to three-fourths of an inch ; length, one to 
two inches. 
Tapes tenerrima , Cpr., Fig. 2, PI. I, is often 
four or five inches in length. It is thin, flat, and 
marked by innumerable fine radiating lines, and 
many small concentric ridges. The cardinal hinge 
teeth are near the anterior extremity of the shell; 
the ligament is long and external ; the pallia! 
sinus is very deep. This species is sometimes 
thrown up from deep water, by storms. Its color 
is white, somewhat yellowish in places. 
Tupellarialamellifera , Conr,, Fig. 4, PI. XIY, 
is a nestler among rocks. It has a strong, white 
shell about an inch in length, and may be easily 
known by the ten or twelve large, thin, concen- 
tric laminae, which mark its sides. It has no ra- 
dial lines, and can thus be distinguished from 
the variety ruder ata, Desh., of Tapes staminea. 
The largest of all that class of mollusks com- 
monly called clams, is known by the name iSchi - 
zothoerus Nuttallii , Conr., though by some it is 
called by the more simple term, u Washington 
Clam.” It is a huge, burrowing mollusk, some- 
