168 AMPHIDROMUS, GROUP VI. 



versus WALLACE, P. Z. S., 1865, p. 412 ROCHEBRUNE, Bull. Soc. 



Philomathique, 1881-1882, p. 71 DE MORGAN, Moll. terr. et 



fluv. de Perak, Bull. Soc. Zool. de France, x, 1885, p. 387. 

 SCHEPMAN, notes from the Leyden Museum, xvii, p. 156 (1896). 

 FULTON, Ann. Mag. N. H. (6) xvii, p. 70. Helix recta MULL., 

 t. c., p. 93, and of Gmelin and Dillwyn Bulimus perversus 

 var. $ PFR., Monogr.,ii, p. 38 Bulimus jay anus LEA, Proc. Amer. 

 Philos. Soc., ii, 1841, p. 31; Obs. Gen. Unio, iv, p. 2. PFR., 

 Monogr., ii, p. 229 Bulimus contusus REEVE, Conch. Icon., pi. 

 37, fig. 220 (Sept., 1848). MOUSSON, Moll. Java, p. 109. Canis- 

 trum contusum FFLD., Verb. Zool.-bot. Ges. Wien, xix, 1869, p. 

 874 (Java) Bulimus elongatus HOMBRON & JACQUINOT, Voy. 

 Pol Sud, pi. 8, f. 3, 4 (1848-1853). 



The typical form of this species is usually sinistral, though dextral 

 shells are on record. It is elongated, with rather slender spire, 

 rather sparse streaks of varying shades of chestnut on a whitish 

 ground, darker below the periphery. The edge of the lip is brown, 

 recurved but not adnate ; and the parietal wall is dark within, with 

 a marginal band of white callus. A. atricallosus is not unlike inversus 

 in many respects, but I can see no sufficient reason for uniting the 

 latter with A. perversus, as some authors have done. 



The name inversus refers to the reversed coil of the whorls, as 

 opposed to recta Milll., a dextral form of the same species, in all pro- 

 bability, though positive information on H. recta is lacking. 



A. inversus has been recorded from Java (' Novara ' exped.) and 

 from Cambodia and Siam (Pavie ; Morlet in Journ.de Conchyl., 

 1889, p. 127). Morlet mentions a var. alba, gJobosa from Tram 

 Khna, between Kampot and Pnom-Penh, and a var. curta from 

 Battambang, Siam. Rochebrune identifies specimens collected by 

 Dr. Harmand on Poulo-Condor as inversus. The specific identity of 

 these forms calls for further confirmation. M. de Morgan did not 

 encounter inversus in Perak. 



Of the specimens collected by the Dutch Borneo Expedition, 

 Schepman says that from Sambas is sinistral, the majority of the 

 others dextral ; nearly all are rather small, measuring only 43^ and 

 45 mill. 



Var. ANDAMANENSIS ( Mousson ' Pfr.). PI. 56, figs. 94, 95, 96, 97. 

 Sinistral, nearly covered perforate, conic-ovate, the spire rather 



