296 HELIX-PLANISPIRA. 



ish or brownish-buff epidermis, here and there regularly and shortly 

 setigerous, the hairs readily deciduous and leaving a golden or silvery 

 impressed point; corneous- white, unicolored or with two brown 

 bands, one above, one below the periphery ; spire depressed, plane, 

 subimmersed in the middle. Whorls 4, subconvex, separated by 

 impressed sutures ; the last whorl large, subconstricted behind the 

 lip and with a gibbous crest ; scarcely descending in front ; with a 

 moderate, penetrating umbilicus. Aperture rotund-lunate, higher 

 than wide, very oblique, white inside ; peristome rosy purple, nar- 

 rowly and equally expanded and reflexed, the margins coverging, 

 columellar slightly dilated and deflexed above the umbilicus. 

 Alt. 8, greater diam. 18, lesser 16 mill. (Tapp. Can.} 

 Shores of the river Fly, Southern New Guinea ; also, shores of the 

 Katau. 



H. plagiocheila TAPP. CAN. Ann. Mus. Civ. Geneva, xix, 1883, p. 

 174, t. 5, f. 4-7, and anatomy, t. 7, f. 6. 



Resembles H. tortilabia in form. It is a third smaller, is flat 

 above, the shell is thinner, is less gibbous behind the constriction 

 at the aperture, the latter is higher than wide ; it especially differs 

 in the epidermis, which in tortilabia is smooth, lucid, thin, closely 

 adherent; that of plagiocheila being velvety, readily coming off and 

 having scattered stiff short hairs. 



H. LEPTOCHEILA Tapparone Canefri. PI. 61, figs. 25, 26, 27. 



Shell umbilicate, discoidal, rather thin, shining, pellucid, obliquely 

 striatulate, white, having a broad, deep chestnut band above ; spire 

 plane, subimmersed in the middle. Whorls 4, a little convex, sep- 

 arated by impressed sutures ; the last whorl subconstricted behind 

 the aperture, then subinflated and obliquely swollen; moderately 

 descending in front ; base convex and subcompressed around the 

 penetrating but little widened umbilicus. Aperture ovate-lunate, 

 wider than high, very oblique; peristome rosy, narrowly expanded, 

 reflexed, margins converging, approximating, columellar slightly 

 dilated and reflexed above the umbilicus. Alt. 7J, greater diam. 

 17, lesser 15 mill. (Tapp. Can.) 



Moluccas. 



H. leptocheila TAPP. CAN., Ann. Mus. Civ. Genova, 1887, p. 150, 

 t. 1, f. 14-16. 



