MELANTHO. 



39 



is extremely short, flattened, but well defined quite to the acute 

 apex ; the sutures are impressed ; the body whirl 

 comprises more than five-sixths of the complete length 

 of the shell ; the aperture is almost as long as the 

 body whirl, and so wide that the length and breadth 

 of the shell are almost equal ; the shell is remarkably 

 globose, almost circular. I have often met in cabi- 

 nets with immature specimens of Viv. pondcrosa under 

 this name. No. 8925 were also labelled regularia by Mr. Lea. 

 His description here follows. The shell figured under this name 

 by Reeve appears to me a young M. ponderosa. 



Paludina regularis, Lea. — Shell subglobose, rather thick, greenish horu 

 color, imperforate ; spire very short ; sutures impressed ; whirls five, con- 

 vex ; aperture large, ovate, within bluish. 



Ohio? T. G. Lea. My cabiuet, and cabinet of T. G. Lea. Diam. .38, 

 length .52 inch. 



A very distinct species with the body whirl about four-fifths the length 

 of the shell. The whirls are very regular, giving the spire somewhat the 

 appearance of a coil of rope. All the specimens before me are more or 

 less incrusted with the oxide of iron. The aperture is inflated, and about 

 three-fourths the length of the shell. 



I am not positively sure that this species came from Ohio. By some 

 accident the label has been misplaced, but I am under the impres.sion it 

 came with some other species from my brother at Cincinnati. {Lea.) 



Ampullaria crassa, of De- Fig. 78. 



shayes, is a synonym of this 

 species, as will be seen by the 

 translation given below of De- 

 shayes' description. He quotes 

 erroneously Paludina crassa, 

 of Say, for the species — Mr. 

 Say never having published 

 this name. An examination 

 of the animal has, moreover, 

 shown it to belong to the genus 

 Melantho. Fig. 18 is taken 

 from a drawing of the animal 

 by Mrs. Say, which Prof Haldeman furnished me. 



AmpuUaria crassa. — Shell ovate-elongate, acute, thick, solid, under the 

 epidermis brownish ; very white ; transversely substriate ; whirls 6, con- 



Animal of Melantho ponderosa. 



