The Notch-side Shells 



P. maesta, Cpr., is found on Southern and Lower California 

 beaches under stones when the tide is out. Its brown shell is 

 strongly cross-ribbed, with beaded and spotted sutures between 

 the whorls. Length, about i inch. 



P. torosa, Cpr., is cross-ribbed along the shoulder of the 

 whorls, the protuberances contrasting with the brown ground 

 colour. Length, over i inch. 



Habitat. — Southern California. 



Genus DRILLIA, Gray 



Allied to Pleurotoma, and closely resembling it, but smaller 

 and more delicately made throughout. Well represented on 

 our west coast. 



The Pencilled Drillia (D. pencillata, Cpr.) I first found alive 

 on the sand at Terminal Island, below San Pedro harbour. It 

 had been a notable day, for I found a large Pomaulax alive 

 on the rocks at Dead Man's Island. The old jetty had yielded 

 living Pectens, Pteronoti, Olivellas, bubble shells, and even a 

 devil-fish of handy size to carry home. My good luck as a col- 

 lector came from having as a guide Mrs. Oldroyd, whose wide 

 knowledge of the molluscan life of the Pacific coast is recognised 

 by all modern conchologists. She had her reward in the discovery 

 of a rare species of Thracia, and in showing a stranger the rich 

 fauna of San Pedro. 



The train was late, and we returned to the beach, for the 

 tide was at its ebb, and daylight still lingered. Well up on the 

 sand we discovered little pellets of sand lifted. Under each was 

 a Drillia, thrusting itself out of the narrow doorway, as if to 

 survey the landscape. The slender spire, the notch, and the 

 close, angled cross lines on each whorl, identified the species. 

 The sutural notch produces the fine herring-bone pattern of 

 brown and yellow that decorates the coils. The largest specimens 

 were under two inches in length. 



Habitat. — Southern California. 



The Knobbed Drillia (D. torosa, Cpr.) is a northern species, 

 much darker brown, with a pale beaded line following the suture. 

 Length, 3 inches. 



Habitat. — California northward. 



D. mcjesta, Cpr., like the last in size and form, substitutes 



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