MARINE UNIVALVES 



135 



Fig. 107. X 5 (*) 



olive, and its length is one inch. A variety from 

 San Pedro is smooth, with fine color lines. 



Drillia empyrosia, Dall, the Burnt 

 Drill-shell, is shown somewhat 'enlarged 

 in Figure 107. It has yellowish whorls, 

 with a burnt sienna brown tint on the 

 later ones, though a paler band shows 

 white patches where it crosses the ribs. 

 It is not found near the shore, but is 

 dredged from deep water off San Pedro. 

 I'urris incisa^ Cpr., the Incised Drill- 

 shell {Drillia incisa), is an inhabitant 

 of Puget Sound. Its shell is similar in 

 shape to Figure 105, but it is smaller, 

 being only a little over an inch in 

 length. Its surface is ash-colored, with reddish re- 

 volving lines. 



The genus Bela includes a large number of small 

 shells, m.ost of them from the north, and some of 

 which are obtained by dredging. They are decidedly 

 spindle-shaped, and many of them have the charac- 

 teristic notch in the outer lip near the upper end of 

 the aperture. On account of their small size or rare oc- 

 currence they will not be farther described in this book. 

 Figure 108 gives an enlarged view of the little 

 Mangilia ??ierita, Gld., the Ribbed Mangilia. It has 

 six whorls and the surface is marked by high cross- 

 ridges and fine spiral lines. It is a whitish 

 shell, very delicate and pretty, and it is usu- 

 ally less than half an inch in length. Its 

 home is on the west coast of Central Ameri- 

 Fig 108 ^^^ ^^^ ^^ reaches as far north as San Diego. 



