o.h 



The Nautilus. 



^<>L. HI. JULY, 1889. No. 3. 



NOTE ON TWO HELICES NEW TO THE FAUNA OF THE UNITED STATES. 



BY W. II. DALL. 



SOME time since, among some shells from Southeastern Florida, 

 received from Mr. G. W. Webster, two small Helices were 

 noticed which a careful comparison with known U. S. forms foiled to 

 identify. By the kind intervention of Mr. H. A. Pilsbry, they 

 were determined to be H. {Microconus) cceca Guppy, described from 

 Trinidad, and H. (if.) granum Strebel, previously known from jNIex- 

 ico. This induced me to overhaul the small species in our collection 

 to see if these forms had by any chance crept in under other names. 

 The result was, that I found H. cjranum, which had hurriedly been 

 referred to Guppy ia Gundlachi, and H. cceca which had been left 

 unnamed probably as the young of something else. 



The localities now known in Florida for the above species are as 

 follows : 



H. ciEca. St. Augustine. (C. H. Johnson.) Near St. John's 

 River and near Lake Worth in East Florida, and near the Hills- 

 borough River, emptying into Tampa Bay, West Florida (ISh: G. 

 W. Webster). Mr. Webster identified this si^ecies as H. diosoricola 

 C. B. Adams, descrilied from Jamaica, and it is very probable that 

 it is at most a slightly larger variety of it, in which case Adams' is 

 the oldest name. 



H. granum. Archer, Alachua Co., Fla. (Dall.) ; Evans' planta- 

 tion, Rogers River (C. T. Simpson) ; vicinity of Lake Worth 

 (G. W. Webster). When perfect this species is nearly the size of 

 H. labyrinthica, very thin, redclish-brot\n, with very deep sutures 



