SHELLS WITHOUT CANALS 



201 



Fig. 193 



found a few living specimens at Monterey, but it is 

 rare so far north. Many of these more uncommon 

 species may be found by wading into the water at 

 low tide, and turning up stones or bringing them 

 out to dry land for closer examination. 



turrit ell a coo peri, Cpr., Cooper's Tower- 

 shell, is shown in Figure 193. This south- 

 ern species has a very slender, many 

 whorled spire. The sutures are distinct, 

 the aperture circular, and the outer lip 

 sharp and thin. The color is yellowish, 

 though it is somewhat spotted with brown. 

 It can hardly be mistaken for any other 

 shell. It is found on sandy beaches be- 

 tween tides. 



^acliyrynclius tenuisculptus, Cpr., the 

 Little Tower-shell, is like a minute speci- 

 men of the last, and is found on mud-flats along the 

 southern coast. The usual length is less than one- 

 fourth of an inch. 



We are now to study the Littorines, or Shore- 

 shells, for that is what the name means. They are 

 the first shells that you commonly meet when you go 

 down to a rocky coast, for they perch high up on the 

 rocks where they will get only a sprinkle of spray 

 now and then, when the waves are quite strong. 

 The}^ do not stay there all of the time, to be sure, 

 and they are quite at home under water; but as a 

 general thing they prefer a roosting place where 

 they will be uncovered most of the time. 



In general the littorines have fairly round shells, 

 about the size of small peas. There is no canal ; but 



