Notes on the Collection 75 



idae and Neritidae and their allies. Nor does it seem 

 best to enumerate the operculate land shells (Trunca- 



TELLIDAE, CyCLOSTOMIDAE, HeLICINIDAE, PrOSER- 



pinidae, etc.) with fifty-eight genera, and over six hun- 

 dred species, carefully studied, fascinating, and worthy 

 of full description. The fresh-water shells not listed 

 are also numerous, choice and beautiful. 



The Turbinidae and Trochidae are of especial 

 interest to collectors and their representatives are worthy 

 of extended mention, but we must be content to notice 

 the nine or more species of Delphinula including D. 

 aculeata, imperialis (a strikingly handsome shell, a very 

 rare species), tyria, incisa, laciniata, atrata, and distorta, 

 and the deep sea forms Bathybembix argenteonitens and 

 Turcicula bairdi, and pass to a family of far more than 

 ordinary importance. Pleurotomaria beyrichii, — last of 

 a noble race, coveted representative of an almost extinct 

 but princely family, the Pleurotomariidae. Even the 

 pearly Nautilus has no higher pride of ancestry, no 

 greater magnificence of apparel. This priceless treas- 

 ure is from the depths of the Japanese ocean. Only 

 five recent species of this family and only seven of the 

 beyrichii are known. The group culminated in num- 

 bers in the Coal Age, and a fossil specimen from that 

 period is in the collection. '■ 



An exceptionally fine series, even for this cabinet, 

 is that of the Haliotidae, with over seventy species, 



