108 AMERICAN JOURNAL 



DESCRIPTION OP A NEW SPECIES OP VIVIPARA. 



BY GEORGE W. TRYON, JR. 



Vivipara Waltonii, Tryon. — t. 10, f. 2. 



Description. — Shell ovate-conic, moderately thick, the surface 

 marked only by growth lines ; spire pyramidal, suture well 

 impressed; whorls 5 — 6, moderately convex, regularly and 

 slowly increasing, the last two-thirds of the total length ; 

 aperture small, rounded oval ; umbilicus scarcely covered by 

 the columellar lip; surface polished, light olive, with revolving 

 bands, which are visible in the interior of the mouth. 



Dimensions. — Length 22, diam. 17 mill., length of aperture 

 13 mill. 



Locality. — St. John's Eiver, Florida. Mrs. Margaretta 

 Walton. 



Cabinet of Dr. E. Michener, Avondale, Chester Co., Penna. 



Observations. — The above species was first observed by Mr. 

 Say, who thus remarks upon it : "Paludina elongata, Swainson. 

 Capt. Leconte presented me with a shell which, he informed 

 me, he found in the Eiver St. John, Florida. I described it 

 nearly four years since under the name of multilineata ; but 

 recently, being about to publish it, on a more attentive exami- 

 nation and comparison with a specimen of the elongata from 

 Calcutta, given to me by Mr. Hyde, of Philadelphia, I have 

 concluded that it varies from that specimen only in having the 

 umbilicus a little smaller." — New Harmony Disseminator, ii. 

 p. 245, Aug. 12, 1829. 



In the "American Conchology," plate x., Mr. Say figured 

 this species under the name of vivipara, Linn., and his figures 

 are copied, with the same name, in Prof. Haldeman's " Mono- 

 graph of the Limniades," pi. vi., f. 3, 4. In the last-mentioned 

 work another figure is given of a young specimen (pi. vii., f. 

 3, 4) under the napae of Bengalensis, Lam. (==elo?igata 7 Swn.). 

 This is from a specimen deposited by Mrs. Say in the museum 

 of the Academy of Natural Sciences of Philadelphia, and 

 believed to be the original specimen received by Say from 

 Florida. 



