88 HELICEA. 



H. DorfeuiUiana Lea varies in size, — the following are the 

 measurements of my largest and smallest specimens: — 



Diara. maj. 8, min. 7, alt. 3^ mill. 

 " " 6^ " 51" 3 



With respect to the shell considered by Shuttleworth to be H. 

 DorfeuilUann, it will be seen from the figure (PL ix. fig. 26), 

 which differs, as he says, from Lea's, that the superior tooth on the 

 labrum is larger and more deeply seated than the inferior one, and 

 that the latter, though more developed, is much of the same form 

 as the inferior tooth in fatigiata and Troostiana. The parietal 

 tooth partakes of the general character of that in Lea's type of 

 DorfeidlUana, but its lower and terminal margins project more 

 perpendicularly from the parietal wall. The umbilical perforation 

 is also larger, and the base of the shell is more smooth. 



The following are the measurements of a large specimen : — 



Diam. maj. 9, min. 8, alt. 4. 



I am much inclined to consider this a distinct species, but remark 

 upon it, as I believe it is more commonly found in cabinets under 

 the name of Dorfeidlliana, than the shell described by Lea. 



H. DorfeuiUiana, and also the shell last considered, have a tuber- 

 cle within, very similar to that \n fatigiata and Troostiana. 



HELIX TROOSTIANA Lea. 



Plate XXXIX. Figure 2. Plate LXXVIII. Figure 11. 



Polygyra Troostiana Lea, \. c. 



Troschel, Ar. f. Nat. 1839, iii. 222. 

 Hdix Troostiana Pfeiffer, Mon. Hel. Viv. i. 419; iii. 267. 



Desha yes in Fei-. i. 75, pi. 69 d. fig. 4. ? 



Chemnitz, ed. 2, i. 376, pi. Ixv. figs. 21-24. 



Reeve, Con. Icon. No. 706, (1852). 



Bland, N. Y. Lye. vi. 288; Notes, 12, pi. ix. figs. 21-23. 

 Belix fatigiata BianEY in B. Journ. 1. c. ; in Terr. Moll., ex parte, ii. 193, pi. 



xxxix. fig. 2. 

 Helix plicata Shuttleworth, Diag. n. Moll. p. 18, (1852). 

 W. G. Binney, Notes, 11. 



A more careful examination of Lea's specimen has 

 convinced me of its specific distinction from plicata. On 

 pi. 18, fig. 11, is a fac-simile of Lea's figure, and his 

 description follows. 



