BY C. HEDLEY. 693 



Archipelago. The chain of evidence is completed by the recogni- 

 tion (P.Z.S., I.e.) of Guppy's specimens as a variety of his G. tristis 

 by Dr. Tapparone-Canef ri, himself. I do not, however, understand 

 why, if the preceding argument be correct, the learned conchologist 

 of the British Museum failed to see Pfeiffer's species, of which 

 he possessed the type, in the specimens labelled " Guadalcanar 

 (MacGillivray) " ; but the loss or displacement of a ticket has 

 originated many such errors. 



Other localities where this widespread and variable species has 

 occurred to Mr. Brazier are — Rubiana, Solomons ; Blanche Bay, 

 New Britain ; and Port Hunter, Duke of York Islands. After 

 this review of specimens and descriptions, I have to plead guilty 

 to adding a third name (Leptopoma parvum ; ante, p. Ill) to the 

 synonymy of the species. The differences presented by the soli- 

 tary shell I collected in Milne Bay from the figure and description 

 published by Tapparone-Canefri, which alone I consulted, sink 

 into insignificance after comparison with further specimens, figures 

 and descriptions. Very close, if not identical with this species, 

 must be the C. novce-hibernce, Pfeiffer. 



In my former article I dealt with the internal distribution of 

 the mollusca of the province whose divisions ' may be briefly 

 summed up as alpine, insular and northern or southern of the 

 axis of the Owen Stanley chain of mountains. A few remarks 

 on the external relations of this fauna have since suggested them- 

 selves. Wallace's line, so conspicuous a severance among the 

 vertebrates, appears to be quite blotted out when the distribution 

 of animals is regarded from a molluscan standpoint. No sharp 

 break occurs between the Malayan fauna as exemplified in Borneo 

 or the Philippines and in New Guinea. All the characteristic 

 Malayan forms, Atopos, Xesta, Helicarion, Microcystina, Trocho- 

 morpha, Obba, Chloritis, Cochlostyla, Pitpina and Diplommatina, 

 are common to both regions. The Solomon Islands, Fiji, Samoa, 

 &c, appear by the light of the Papuan shells to be inhabited by 

 an eastern extension of this Malayan fauna, which has also over 

 flowed into Queensland. 



