HYALINA. 399 



umbilical region deeply excavated, but not perforated, with very 

 few exceptions, the lip usually terminating at the central point. 

 Diameter one fifth of an incli, sometimes more. 



Animal Ijluish-black upon the upper parts ; margin and posterior 

 extremity lighter. 



Found in company with H. arhorra and H. stnafelJa, about de- 

 caying stumps and logs. At Oak Island, in Chelsea, I have found 

 it abundantly. It inhabits all of Eastern North America, having 

 l)een found from Canada to Texas and from Dacotah to Florida. 

 It is also said to occur in St. Domingo. 



This species is of about the same size as H. arborea. Its color 

 is much lighter, its apex less depressed, its whorls less in number 

 by one, the outer whorl increases much more rapidly, its umbilicus 

 is usually closed ; and, moreover, the impressed lines, which look 

 like water lines, or the lines on a gooseberry, apparently radiating 

 from the umbilicus, are entirely characteristic, and distinguish it 

 from every other species. They are not readily discerned without 

 a magnifier. 



*'C5^ 



Hyalina minuscula. 



Shell depressed-convex, whitish ; whorls four ; aperture nearly circular ; lip 

 simple ; umbilicated. 



Helix minuscula, Binney, Best. Journ. Nat. Hist. iii. 435, pi. 22, fijj. 4 (1840) ; Terr. 



Moll. ii. 221, pi. 17ffl, fig. 2, excl. syn. — Adams, Vermont ISIoll. 161 (1842).— 



Chemnitz, 2d cd. ii. 112, t. 85, figs. 20-23. — Pfkiffer, Symbol, ii. 33; Mon. 



Hel. Viv. i. 114. — Reeve, Con. Icon. 731 (1852). — W. G. Binney, Terr. Moll. iv. 



102. — Morse, Anier. Nat. i. 543, fig. 35 (1867). 

 Helix minutalis, Morelet nee Fer. Test. Nov. ii. 7. 

 Helix apex, Adams, Cont. Conch. 36. — Reeve, 1. c. 339. 

 Helix Lavelleana, D'Orbigny, Moll. Cuba, in text, 161, excl. pi. (1853). 

 Helix Mauriniana, D'Orbigny, 1. c. in pi. 8, figs. 20-22, excl. text. 

 Pseudo-hynliiia minuscula, Morse, Journ. Forth Soc i. 16, fig. 34 ; pi. 7, fig. 35 (1864). — 



Tryon, Am. Journ. Conch, ii. 264, pi. 4, fig. 62 (1866). 



Shell umbilicated, minute, depressed-convex ; epidermis pj^ ggg 

 whitish ; whorls four, convex, not increasing rapidly in di- 

 ameter, with microscopic wrinkles ; suture very distinctly 

 impressed ; aperture nearly circular, peristome thin, acute ; 

 umbilicus large, not spread, deep, and exhibiting the volu- 

 tions ; base rounded, columella with a thin callus. Greater 

 diameter two and a half, lesser two and one third, height 

 one millimetres. 



From the Red River of the North to Texas and Florida. It may 



