288 Remarks on Certain Species of 



For fine specimens of II fatigiata Say from Tennessee, I am 

 under obligation to the late Judge Tappan, and to Mr. J. G. 

 Anthony. 



Helix Troostiana Lea. 



Plate IX. Fig. 21-23. 



Synonymy. 



Polygyra Troostiana Lea Trans. Am. Phil. Soc. VI. p. 107. PI. xxiv. 



fig. 119. 1838. 



Helix fatigiata Binn. Bost. Jl. III. p. 388, ex parte (excl. Syn.) — pi. 



xix. fig. 3. 1840. 



Troostiana Pfr. Mon. Hel. I. No. 1088. 1848. 



" Desk, in Fer. Hist. I. p. 75, tab. 69 D. fig. 4 ? 



" Chemn. ed. 2, Helix I. p. 376, tab. 65. fig. 21-24. 



fatigiata Binn. Terr. Moll. II. p. 193 ex parte (excl. Syn.) 1851. 



j)licata " " " III. tab. xxxix. fig. 2. 



Troostiana Rv. Conch. Icon. Helix. No. 706. pi. cxx. fig. 702. 



1852. 

 plicata Shuttl. Diag. n. Moll. p. 18 (Bern. Mitth.). 1852. 



Lea's description and remarks are as follows : — for copies of 

 his figures see PI. IX. fig. 21, 22. 



" Polygyra troostiana. 



"T. superne subplanata, inferne subinflata, cornea, longitudinaliter 

 striata, late umbilicata, ; anfr. 6 ; apertura lunata, tridentata. 



" Shell above nearly flat, below somewhat inflated, horn color ; longi- 

 tudinally striate, widely umbilicate ; whorls 6 ; aperture lunate, three 

 toothed. 



" Habitat. — Tennessee. Prof. Troost. 



" Diam. .4, Length .2 of an inch. 



"Remarks. — This species strongly resembles P. DorfeuilUana, herein 

 described, being nearly of the same size, and possessing most of its cha- 



