PLACOSTYLUS, NEW CALEDONIA. 43 



milk-white, the ends joined by a moderately thick white callus, bear- 

 ing a median tubercle; collumellar margin a trifle folded, dilated, 

 almost completely closing the umbilical chink ; basal and outer 

 margins thickened and somewhat reflexed. 



Length 70, diam. 36 mill.; aperture with peristome, 33 mill, long, 

 25 wide (Crosse). hie of Pines (Lambert). 



Placostylus leucolenus CROSSE, Journ. de Conchyl., xliii, 1895, p. 

 80, pi. 5, f. 6. 



This form bears some resemblance to P. jibratus and its variety 

 cicatricosus, but with the following differential characters : the shell 

 substance under the cuticle is entirely white, as are the peristome 

 and interior ; the columellar fold is but slightly developed, and there 

 is a minute umbilical chink. As it was described from a single shell, 

 which, moreover, had suffered an injury in the third whorl, somewhat 

 altering the form of those following, I do not think the specific rank 

 given by M. Crosse likely to be sustained. 



Var. danieli Crosse. (PI. 15, figs. 13, 14.) Cuticle olivaceous- 

 chestnut, persistent ; lip thickened, slightly sinuous above and below ; 

 parietal nodule slight, the columellar fold rather strong ; last whorl 

 peculiarly contracted backward and to the right. Aperture vivid red 

 within, the peristome ivory-like. Length 80, diam. 33 mill. 



Var. knoblauchi Kobelt. (PI. 18, fig. 34). A very large form, 

 rudely rugose-striate, malleated and indistinctly lirate spirally ; 

 fleshy -reddish under a thin brown epidermis which is indistinctly 

 banded above; suture white-edged, strongly ascending toward its 

 termination. Aperture vinous-brown inside ; columella with a strong 

 twisted fold, separated from the parietal wall by a distinct sulcus ; 

 peristome fleshy-orange, thick ; the orange parietal callus bearing a 

 conic tooth. Length 124, diam. 56, aperture 68 mill. 



Var. insignis Petit. (PI. 25, figs. 17, 18). A very small form, 

 length 65 mill., with 6-7 whorls, the columella with a strong fold, 

 parietal wall bearing a nodule ; apex more or less deep colored in- 

 side ; lip moderately thick. 



Var. ouensis Gassies (PL ,45, fig. 7). An elongate form with pale 

 aperture, measuring 86 mill, long, diam. 41, aperture 44 mill. Its 

 prominent features are said to be the acute spire and dilated base, 

 the expansion of the peristome, and the yellow striate arid malleated 

 epidermis, with triangular white spots. It is said by Gassies to be 

 from the Islet of Uen, south of New Caledonia. Layard procured 

 it at the Isle of Pines. 



