GASTEROPODA. 39 
penultimate whorl superiorly. A thick callus crosses the penultimate 
whorl, and is so arranged as to produce an oblique, microscopic tooth 
at the upper angle of the aperture, in the adult. 
Diameter one-fourth of an inch; axis one-tenth of an inch. 
Obtained on the mountains beyond the valley of Amancaes (Lima), 
under stones. [J. P. c. ] 
This is a miniature H. concava, remarkable for the peculiar pro- 
trusion of the lip, which is also white and a little thickened. ‘The 
umbilicus is larger than in H. pusillus. It may possibly be H. trochi- 
lionides, D’Orb., (Amer. Merid. Moll., 251, pl. 27.) 
Heix tyrata (Couthouy) Gould. 
Testa minuta, depressa, rufo-cornea, umbilicata: spira anfractibus qua- 
tuor cylindracets, et striis elevatis confertis lyratis ; suturd canalicu- 
lata: apertura circularis ; labro simplict. 
Hehz lyrata (Couthouy, MS.,) Goutp; Proc. Boston Soc. Nat. 
Hist., ii. 167. Aug. 1846. Pretrrer; Monog. Helic. Viv., i. 101. 
Expedition Shells, 19. 
Animat dark brown on the back, passing into slate-colour down 
the sides; beneath pale slate-colour. Body covered anteriorly with 
lozenge-shaped granulations. ‘Tentacles moderately long, rather stout, 
eyes large. Respiratory orifice very small, near the median margin 
of the collar. 
SHELL minute, depressed, brownish horn-colour, somewhat mottled 
with cinereous rays. Suture channelled: Whorls four, or a little 
more, nearly cylindrical, their surface delicately barred with minute, 
crowded, rib-like strie. Aperture nearly circular, modified by the 
penultimate whorl; lip simple. Umbilicus of moderate size, but dis- 
tinetly showing the rounded walls of all the whorls. 
Length of the axis one-twentieth of an inch; diameter one-fifth of 
an inch. 
