100 HELICEA. 



HELIX LIMATULA Binney vol. ii. p. 219, pi. xxx. fig. 2. 



Has also been detected in Michigan. 



HELIX MINUTISSIMA Lea. 



Plate LXXVII. Figures 6, 7. 



synonyms and references. 



Helix minutissima Lea, Trans, ditto, vol. ix. p. 17. 



Teoschel, Ar. f. Nat. 1843, ii. 124. 



Pfeiffer, Mon. Hel. Viv. i. 87; iii. 83. 

 Helix minuscula teste Binney, vol. ii. p. 221. 



Anthony, Ohio Cat. Jan. 1843. 



There is every reason for reversing the decision of the 

 identity of this and minuscula, expressed by Binney and 

 Anthony. Lea's original specimen is figured in the plate 

 from a drawing by Dr. Leidy. I give Lea's description 

 below. The shell is readily distinguished from minuscula 

 by its smaller size, less expanded umbilicus, minute striae, 

 and its greater resemblance in outline to H. chersina. 

 Lea's specimen came from Ohio. It has been sent me 

 from Greenwich, N. Y., by Dr. Ingalls. 



Though considered in the Terrestrial Mollusks as a va- 

 riety only of minuscula, I find a note taken by my father at 

 Mr. Lea's collection, in which he says it is 7iot the same. 



This is our smallest shell, being one-fourth less in diam. 

 than H. exigua St. The umbilicus is wide, and shows 

 some of the interior volutions — though not so expanded 

 as H. minuscula or exigua. The apex is distinctly and 

 readily seen in the two last, and the suture is very much 

 more impressed. H. minutissima has delicate striee, but 

 no ribs. The spire is variable in height. 



Helix minutissima Lea. T. subglobosa, supra obtuso-conoidea, subtus 

 convexa, fusco-cornea, minutissime striata, umbilicata ; suturis impressis ; 

 anfr. 4, rotundatis; apertura subrotundata, lab. acuto. Cincinnati. 



Diam. .06, length, .04. It is the smallest species of our country which 

 has come under my notice. Its very minute longitudinal striaa can only 



