342 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



side cusps also, I presume, with cutting points, though none are shown in 

 Morse's figure. Laterals like the centrals, but asymmetrical by the suppression 

 of the inner side cusps and cutting i)oints. Marginals low, wide, the broad re- 

 flection equalling the base of attachment and irregularly denticulated, as in 

 Pupa. 



There are two European species of this genus, A. aculeata and lamellata, 

 whose jaw is described by Lehmann as rather striated than ribbed. Their 

 lingual dentition presents no generic differences from that of harpay though the 

 cusps of the centrals are described as simply conical. 



Acanthinula harpa, Say. 



Vol. III. PI. Lll. Fig. 3. 



Shell subperforate, ovately conic, transparent, very thin, with coarse, irreg- 

 ular lines of growth, pellucid, light horn-color; spire conical, rather obtuse; 

 whorls 4, convex, the upper ones smooth, the two last with prominent, distant, 

 thin, colorless, fold-like ribs, slightly inclined backwards, the last whorl rounded, 

 somewhat longer than the spire ; columella subreceding ; aperture lunately 

 oval ; peristome simple, straight, its columellar termination briefly reflected 

 above. Greater diameter, 2 mill. ; length, 3^ mill. ; aperture. If mill, long, Ij 

 mill. wide. 



. Helix harpa, Say, Long's Exped., II. 256, PI. XV. Fig. 1 (1S24) ; Binney's ed., 



29, PL LXXIV Fig. 1.— W. G. Binney, L. & Fr.-W. Sh., I. 156 (1869). — 



Gould and Binney, Inv. of Mass., ed. 2, 427 (1870). 

 Twpa costulata, Mighels, Proc. Boat. Soc. Nat. Hist., I. 187 (1844). 

 BiUimus harpa, Pfeiffer, Zeitsehr. f. Malak., 1847, 147; Mon. Hel. Viv., 11. 



150 ; in Chemnitz, ed. 2, No. 305, Pl. LX. Figs. 17-19. —Reeve, Con. Icon., 



No. 596 (1849). —Binney, Terr. Moll., II. 290, PI. LII. Fig. 3. — W. G. 



Binney, Terr. Moll., IV. 135. 

 Zoogenites harpa, Morse, Journ. Portl. Soc., I. 32, PI. I. Figs. 1-14 (1864); 



Amer. Nat., I. 608, Figs. 50, 51 (1868). — Tryon, Am. Journ. Conch., III. 



311 (1868). 

 Helix AmurermSt Gerstf., teste Morch. 



A circumpolar species, in our country found in the Northern Region, — Gaspe ; 

 Maine ; New Hampshire. Originally found by Say on the expedition to St. 

 Peter's River, etc. In British America, English River, and James' Bay ; in 

 Europe, Sweden (Mai. Blatt. 1867, p. 200), Norway, Lapland, etc. ; in Asia, 

 Petropaulouski in Kamtschatka. 



Animal small, compared to the size of the shell ; body and head slate-color, 

 eye-peduncles darker, short, thick, bulbous ; eyes large, distinct ; foot but two 

 thirds length of shell, whitish; the body, disk, and mantle are marked with white 

 dots, the edge of the mantle is of the same color as the head and eye-peduncles. 

 The disk is rounded posteriorly, and broad and truncated anteriorly ; the lateral 

 borders are deeply crenulated. The head is separate from the disk, as in the 



