18 



Thus there are at present known, in the United States, 

 thirteen species of this genus. They are remarkable, as com- 

 pared with those found in other countries, for their minute- 

 ness ; the two largest species, armifera and badia, scarcely ex- 

 ceeding in size the smallest of the European species. It is 

 also singular that no species of the allied genus Clausilia, so 

 abundant in Europe and Asia, should have been found, as 

 yet, on the North American continent ; and indeed I am not 

 aware that any shell possessing a true clausium has been found 

 in any part of America. 



The following shell, being figured on the same plate with 

 the preceding, the description of it may be desirable here. 



PUPA LYRATA. 

 PI. XVI. fig. 16. 



Testa parva, plerumque sinistrorsa, castanea, lat umbilicata; anfr. 5 convexis, 

 costulis flexuosis ad 20 concinne clathratis ; apertura sub-orbiculari, campanulata, 

 postice dentibus duobus lamellosis, in faucibus duobus alleris, armata. 



Shell minute, generally reversed, ovate, of a chestnut color ; 

 whorls five, convex, crossed by about twenty delicate, round- 

 ed, flexuous ribs, which give the surface an elegant appear- 

 ance. Spaces between not striated. Aperture somewhat 

 orbicular, the peristome having an inflection posteriorly, 

 against which is a lamellar tooth winding under the trans- 

 verse lip, and another still larger between it and the umbilical 

 region. There is also a thickening at the middle of the outer 

 lip from whence arises a compressed fold which revolves 

 within the aperture, directed between the two teeth on the 

 transverse lip ; and another parallel to this, stretching be- 

 tween the outer anterior and inner posterior angles of the 

 aperture. Umbilicus large and deep. 



Length ^ breadth 5 X D 3 S inch. 



Found at the island of Maui, one of the Sandwich islands. 

 Like most other land shells found there, the volutions seem 

 to be directed right or left indifferently. It is a beautiful 

 shell, and cannot well be confounded with any described 

 species. 



