50 AMERICAN JOURNAL 



and modifying tlie peristome; aperture liiglier than broad, 

 roundly lunate, produced below; bluisli within ; peristome 

 simple,"^ acute, sinuous, angular above at the termination of 

 the carina. 



Greater diameter, including aperture, 22 mill.; length, 35 

 mill. ; length of the aperture, 20 mdl. ; diameter, 10 milli- 

 metres. 



Operculum horny, concentric. 

 Ilalitat^ Huntsville or Stevenson, Alabama. — Dr. W. II. 

 DeCamp, 1st Michigan Vol. Engineers. 



This species was given me by Mr. A. O. Currier, of Grand 

 Eapids, Michigan, who suggested its bearing the name of its 

 discoverer. 



About a dozen specimens were collected. All but the one 

 drawn in plate 7, fig. 3 could not be distinguished from Melania 

 ■without the presence of the operculum, thus furnishing 

 another example of the impossibilit}^ of ascertaining from the 

 shell alone the generic position of some species. It is probable 

 other species of Melqntho have been described as Melanise. 



Fig. 2 was photographed from nature on wood. It repre- 

 sents the largest and oldest specimen. Fig. 3 is drawn from 

 a younger individual. 



Cylindrella coahuilexsis, Binney. — t. 7, f. 4, 5. 



Descript'on. — Shell rimate, cylindrically ventricose, thin, 

 smooth or delicately striate on the upper whirls, strongly 

 ribbed on the last two; white, composed of twelve ventricose 

 or flattened whirls ; apex obtuse, shining, upper three whirls 

 of about equal diameter and smooth, the next four rapidly 

 increasing in width and striate, the next whirl the widest 

 of all and smooth, the remainder very rapidly decreasing in 

 diameter towards the attenuated base ; last whirl with about 

 ten elevated ribs, not cgirinated below, and appressed against 

 the shell so as hardly to be rimate, until extended beyond it, 

 and ending in a continuous peritreme expanded around the 

 subquadrate aperture. 



Greatest diameter, 7 ; length, 29 millimetres. 

 Habitat, Cienga Grande, Coahuila. Four specimens are pre- 

 served in the collection of the Smithsonian Institution. 

 Plate 7, fig. 5, is an enlarged view of the apex of this spe- 

 cies. It belongs to the sub-genus Gongylostoma. 



Oenus Carinifex, Bmney.— t. 7, f 6, 7. 



Description. — Jaws — ? Lingual membrane — ? Tentacles — ? 

 Mantle — ? 



Shell, dextral, spiral, somewhat triangular, strongly cari- 



