74 SERPULORBIS. 



Several specimens are frequently found near one 

 another. The shell is often angular and roughened ; 

 the aperture is circular, and is one-eighth of an inch 

 or less in diameter. The color, as in several of the 

 following specimens, is a dingy white. 



Serpulorbis ^^2/<3';;/2^^r?^5,Cpr.,Ser-pu-lor'-bis squam- 

 i-je'-rus. Very irregular ; frequently many specimens 

 grow together upon a rock, and look like a heap of 

 contorted snakes. The shell is marked throughout 

 its length by transverse, scaly ridges. The aperture 

 is circular, one-fourth of an inch across. The tube, 

 if straightened, would measure some four inches or 

 more in length ; it has a circular operculum. I found 

 a few living specimens of this species 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. A pair 

 of long rubber boots will be found very convenient 

 on such excursions. 



There is a series of shells, dead specimens of which 

 are abundant, which present a puzzling aspect, and 

 which vary greatly in outward appearance. They 

 are not spiral, but appear like hollow cones more or 

 less flattened, with the apex to one side of the center. 

 Some of them are singularly like a horse's hoof in 

 shape, hence they have received a name, derived from 

 the Greek, which has that meaning. 



The number of true species which belong to this 

 coast is somewhat uncertain, on account of the vari- 

 able nature of the shell. I will mention two, which 

 will probably include all our common specimens. 

 The first one is named Hipponyx antiquatus, Linn., 



