54 THE NAUTILUS. 



sometimes there is also a superior palatal ; surface with very fine 

 irregular striae, somewhat shining. 



Size: alt. 1.5-1.6, diam. 1.1 mill., apert. alt. 0.6 mill. 



Soft parts : they could not be fully examined. The dried body of 

 a specimen accidentally crushed was softened up, and showed a con- 

 siderable amount of dark pigment. Jaw yellow, rather narrow 

 (means really : short), slightly curved, with a shallow indentation in 

 the middle of the front edge, the lateral ends produced backward, in 

 curves, like horns ; the surface shows several (4-5) sharp, fold-like 

 ribs on either side, of unequal sizes. Radula : rather broad, with 

 13 + C + 13 teeth, about seven being laterals, the outer three or 

 four marginals, Nos. 8 and 9, about, marking the transition. The 

 central tooth, with its plate almost square, is tricuspid, the medium 

 cusp being about half the length of the plate, the outer ones much 

 smaller ; the first to third, or fourth laterals are bicuspid, but many 

 of the teeth show, more or less distinctly, a minute third, inter- 

 mediate tooth ; the fourth or fifth, to eighth, are tricuspid with the 

 cusps small and the mesodont at last hardly larger; from the tenth 

 on, the cusps gradually disappear. Other parts of the body were 

 not clearly distinguishable or not well defined. 1 



Habitat : Warwick, Rhode Island, collected by Mr. J. Francis 

 Perry. 



The present species resembles the low form of Vertigo ventricosa 

 Mse. in the shape and size of the shell, but the formation of the 

 aperture and its lamellae and folds is quite different, the color is 

 deeper and the surface less shining. From the other three described, 

 typically three-toothed eastern vertigos : tridentata "Wolf, oscariana 

 Sterki and parvula Sterki, V- Perryi is also very different ; in all 

 of the three, the parietal lamellae and palatal folds are much larger, 

 longer, and of whitish color ; the aperture is higher than wide ; the 

 shells are more elevated and of lighter color. 



A new Vertigo from New England certainly is a surprise, 

 and it is the more remarkable for being of a type rather different 

 from all our other Eastern species. No doubt careful search will 

 bring it to light from other localities. I take pleasure in naming 

 the species in honor of its discoverer. 



1 In what appeared to be the mantle, or the pulmonary cavity, there was a 

 small, evidently parasitic, worm, coiled up, the larva of a nematode, as it 

 seemed. 



