58 PLACOSTYLUS, NEW CALEDONIA. 



384, 1870 Placostylus porphyrostomus KOBELT, Conch. Cab. (edit. 



2), Placostylus, p. 50, pi. 12, f. 2-5 ; pi. 13, f. 2, 3, 1891 CROSSE, 

 Journ. de Conchyl., 1894, p. 270. 



Bulimns sinyularis MORELET, Test. Nov. Australia?, p. 2, in Soc. 

 Hist. Nat. Moselle, 1857 Bulimus porpliyrostomus, var. singnlaris, 

 GASSIES, Faune, i, p. 44, pi. 4, f. 4, 1863 ; ii, p. 77, 1871. Buli- 

 mus porphyrostomus, var. j3 constricta, CROSSE, J. de C., xii, p. 119, 

 1864. 



Bulimus porpJiyrostomus, var. abbreviata, GASSIES, Faune, ii, p. 

 77, 1871. 



The original specimen was immature, resembling my fig. 32 of pi. 

 28. With full maturity the cuticle completely disappears, or only 

 some shreds remain ; the lip thickens, the colnmella develops a 

 heavy oblong or squarish callous tooth, and a tubercle appears on the 

 parietal wall. 



The form from the island of Nou is smaller, with darker, more 

 persistent epidermis. Gassies mentions a var. abbreviata as " ovi- 

 form, with buff-brownish epidermis." 



Var. singularis Morelet. (PI. 28, fig. 36.) The type is an old 

 shell with strongly oblique aperture, narrowed and constricted by the 

 thickening of the peristome ; parietal tooth and columellar fold want- 

 ing. It is more extreme than the figure from Gassies shows, ac- 

 cording to Crosse. 



Var. DEBEAUXI (Gassies). PL 28, fig. 35. 



Always perforate, with more regular, wider and open aperture, 

 which is not placed so obliquely as in porphyrostomus ; outer lip and 

 columella less calloused, the former hardly sinused above. Alt. 78- 

 80, diam. 36 mill. Isle of Pines (Lambert). 



Bulimus debeauxi GASS., Faune, ii, p. 184 (1871); Journ. de 

 Conchyl., p. 337, pi. 9, f. 4 (1881). P. debeauxi CROSSE, J. de C., 

 1894, p. 272. 



P. MONACKENSIS (Crosse). PI. 27, figs. 26, 27. 



" Larger than P. duplex, with the aperture paler inside, pale 

 tawny ; peristome strongly thickened, milk white. Length 79, diam. 

 35, apert. with perist. 38 mill, long, 25 wide." 



Monack Island (type locality, Rossiter); Isle of Pines (Marie). 



Placostylus duplex var. monackensis CROSSE, Journ. de Conch. 



