THE NAUTILUS. 65 



crowded ribs narrower than their intervals ; ribs slightly bent for- 

 ward at the suture, 32 to 36 on the penultimate whorl in average 

 specimens. Whorls about 10, very slightly convex, the last ascend- 

 ing in front. Aperture vertical, slightly flesh-tinted inside ; peri- 

 stome white, thick, well reflexed, terminations slightly approaching; 

 parietal callus heavy, appressed. Parietal tooth narrow and very 

 short, about ^ mm. high, axial fold moderate. 



Smallest, length 19^, diam. 10, aperture 8^- x 7| mm., whorls 9, 

 ribs 33. 



Largest, length 27|, diam. 13, aperture 11^ x 9| mm., whorls 10> 

 ribs 37. 



Average length 24^, diam. 12, aperture 10 x 9 mm., whorls 10, 

 ribs 36. 



There is considerable variation in the number of ribs, as a speci- 

 men 21|x 10^ mm. has 38, one 22 x 11| has 42, and one 27^ x 12 

 has only 31. 



Plate IV, figs. 9, 10. Over 200 shells have been examined. 



Southern end of North Bimini Cay, Bahamas, May, 1912. 



These shells were collected on the extreme southern end of the 

 Cay on young sisal plants. From 15 to 30 shells could be gathered 

 from a single plant. An occasional specimen was picked up under 

 or on the " sea-grapes," but it appears to be confined to the southern 

 point of the island, as further up only an occasional dead " crab- 

 shell " was found. About three-quarters of these shells are cleaned 

 perfectly, and these are considerably lighter than the ones in which 

 part of the animal remains. By accident only two young examples 

 were saved, and these show no sign of internal teeth. In collecting 

 we noticed that a number of the adult shells had the lower part of 

 the lip bitten off, as if some rodent had attacked them at that point. 



NEW SPECIES OF CLAUSILIA AND PARTULA FROM THE COLLECTION 



OF MR. J. S. EMERSON. 



BY H. A. PILSBRY. 



When looking over the fine series of Hawaiian shells in the col- 

 lection of Mr. Emerson in Honolulu, I had opportunity to note the 

 presence of many shells foreign to the islands. Among them there 

 is a good series of land shells collected by him in Europe, and many 



