GASTROCOPTA, NORTH AMERICA, WEST INDIES. 23 



Rep. on Expl. in Neb. and Dak., in 1855-57, reprint, 1875, 

 p. 107 (Ft. Berthold; name only). "Pupa nebrascana War- 

 ren's Rep. of Surveys, etc., Ex. Doc., ii, pt. 2, 35th Cong., 

 1859, p. 725"; W. G. BINNEY, Terrestrial Moll., v, p. 213 

 ("may perhaps be P. contracta"). 



This species is readily known by the conic shape, and pecu- 

 liar aperture, nearly closed by the large teeth. There is some 

 variation in the shape, some individuals being more shortly 

 conic than that figured. Also in the prominence of the low 

 ridge or crest behind the outer and basal lips, which varies 

 from strong to very weak. 



Its western limit, as represented in the collection of the 

 Academy, is Clay Co., South Dakota, Payne Co., Oklahoma, 

 and mouth of the Pecos River, Val Verde Co., Texas. South- 

 ward it extends over peninsular Florida in a slightly different 

 race, but has not occurred on the keys of the southern and 

 eastern coast. 



In the higher parts of the Alleghaiiy Mountains, G. con- 

 tracta seems to be rare, if not absent. 



In Mexico specimens are in the collection of the Academy 

 from Tampico, Tamaulipas; several places in eastern San 

 Luis Potosi; Yautepec, Morelos; Texolo and near Orizaba, 

 State of Vera Cruz; the specimens collected by A. A. Ilink- 

 ley, S. N. Rhoads and the Heilprin expedition. 



In Jamaica G. contracta was found by C. B. Adams prior 

 to 1850, and subsequently it was taken in the interior of St. 

 Anne (C. P. Gloyne, Journ. de Conch., xxiii, 1875, p. 121), 

 near Hope Bay (H. Prime, in Henderson coll.) and on Swift 

 River (C. W. Johnson). Specimens from all these lots have 

 been examined. Possibly it was introduced on plants from 

 the mainland, Mexico or the United States, as the species 

 seems an alien in the Jamaican fauna; yet its occurrence in 

 several localities is against this view. I cannot see that the 

 Mexican and Jamaican specimens differ in any way from 

 those of the United States. It is a wonderfully constant 

 species. 



