CHAPTER X 
SHELLS WITHOUT CANALS 
My first opportunity to gather any of 
the shells described in this book occurred 
in 1877. The place was a shallow arm of 
San Francisco Bay, and the shell was 
the one shown in Figure 229. I shall 
never forget the pleasure I felt as I saw 
ZY them lying by dozens and hundreds on 
Fig. 229 the surface of the mud, after the tide had 
gone down. They seemed to be enjoying the fresh 
air, and displayed no anxiety for the return of the 
tide. Similar species in other countries spend so 
much of their time in the air, that they have been 
mistaken for land shells. 
The name of this species proved to be Cerithid- 
ea californica, Hald., the California Horn-shell 
(C. sacrata). But at first I was as ignorant of the 
proper care of the shells as I was of their name, 
and a pretty source of trouble they were to me, for 
I had not then learned how to clean them prop- 
erly, a process which has already been explained 
on a previous page. 
The shell in question is an inch or more in 
length, and consists of about ten strongly ribbed 
whorls. The outside is dull and black, but the in- 
side is of a glossy brown. The aperture is entire, 
