"^ 



312 A MANUAL OF AMKRTCAX LAND SHELLS. 



mcsodon dentiferus, Bixnky. 



Shell imperforate, flattenedconvex on tb^ upper surface, convex be- 

 low ; epidermis yellowish horn-color, immaculate ; spire 

 depressed ; whorls 5, with delicate, parallel, oblique 

 striai; suture distinct, not deeply impressed ; aperture 

 contracted by the i)eristome, flattened towards the 

 plane of the base; peristome thickened, white, broadly 

 and abruptly reflected ; parietal wall with a prominent, 

 white, tooth- like process, nearly parallel with the lower 

 margin of the aperture, not projecting towards the um- 

 M. dentiferus. bilicns ; basc convex. Greater diameter 23, lesser 

 IS"""; height, 10""". 



Helix dentifera, Binney, Bost. Journ. Nat. Hist., i, 494, pi. xxi (1840) ; Terr. Moll., ii, 

 134, pi. xii. — Adams, Vermont Mollusca, 159 (1842).— Pfeiffer, Mou. Hel. 

 Viv., i, 317.— W. G. Binney, Terr. Moll., iv. 55 ; L. & Fr.-W. Sh., i, 145 (1869). 

 — DeKay.N. Y.Moll., 34, pi. ii, fig. 17(1843).— Mrs. Gray, Fig. of Moll. Ann., 

 pi. cxci, fig. 11, no (laser, (from Bo.st. Jonrn.). — Morse, Amer. Nat.,i, 99, figs. 

 6, 7 (1867).— Gould an«l Binney, Iuv. of Mass., ed. 2,4-24 (1870).— Pfeiffer. 

 Mon., V, 429 (18()8).— Not of Pfeiffer, iii.— Not of Chemnitz, ed. 2 (—Roemeri), 



Mesodon dcutifera, W. G. Binney, Terr. Moll., v, 328. 



From Maine to Ohio and North Carolina. It prefers mountainous 

 country. It may be considered a species of the isorthern Region, rang- 

 ing into the Interior Eegion, especially along the Appalachian Chain. 



On Sugar Loaf Mountain, 30 miles east of Roan Mountain, North 

 Carolina, Mrs. Andrews fonnd a specimen with 5| whorls, greater 

 diameter 30, lesser 25; height, 12""". 



Readily distinguished from the allied species by the very angular 

 and broad reflection of the peristome. 



Animal grayish on the sides and posterior extremity, brownish on 

 the upper parts, darker on the head and neck; foot long and narrow; 

 eye-peduncles long and slender: eyes black. (See Bost. Journ. Nat. 

 Hist., I, Plate X.) 



Jaw as usual in the genns ; 14 ribs. 



Lingual membrane (Terr. Moll., Y, Plate VIII, Fig. J) with 32-1-31 

 teeth, with 15 laterals. 



Genital system (Ann. N. Y. Ac. Nat. Sc, I, Plate XIY, Fig. G): The 

 genital bladder is small, oval, on a short duct, which is greatly swollen 

 at a short distance below the bladder; the penis sac is long, stout, and 

 contracted at a short distance below its blunt end ; the retractor is 

 inserted on the vas deferens at about the middle of its length. In 

 another specimen the penis sac was less constricted. 



