288 ME. GUY C. EOBSON ON MOLLUSCA 



to trace the influence of the surrounding molluscan faunas upon the island and its 

 several suhregions ; while Hedley laid down the broad principles of its relationships, 

 laying stress on its Oriental rather than its Australasian character, in opposition to Cooke 

 (' Cambridge Natural History: MoUusca'), who had emphasized the latter. Exami- 

 nation of the present collection, though the precise position of the two new Zonitoid 

 genera is as yet unsettled, tends to confirm Hedley's view. The occurrence of a probably 

 new Biplommatina and two new genera of Zonitoids points to Continental Asiatic rather 

 than to Australian affinities. But generalizations upon the molluscan fauna of this, as 

 of all other countries, must await the coming of more ample anatomical knowledge. 

 The experience of many workers could be quoted which goes to show that speculations 

 upon the affinities of various faunas based upon conchological characters are frequently 

 unreliable and inadequate. There is urgent need for more anatomical knowledge, and 

 until this is forthcoming, and until our conchologists turn anatomists, the real position 

 of the molluscan fauna of New Guinea and of its several political divisions — Dutch, 

 British, and German — must, to the scientific mind, remain unresolved. 



Of the new forms described here the genus for which the name Chronos is proposed 

 is specially interesting, as much for the great altitude at which it was obtained 

 (viz. over 14,000 ft.) as for its anatomy. Mollusca from the higher ranges in New 

 Guinea have already been recorded (cf. Kobelt, Nachrichtsbl. Malakozool. Ges. 

 1913, Heft ii. p. 87), one of which came from over 12,000 feet. The author is not 

 aware of any instance of Mollusca being obtained at greater altitudes than that 

 here recorded. 



It is significant that the two new genera obtained from the high mountains off'er 

 considerable difficulty with regard to their systematic position, though it should be 

 pointed out at the same time that the Sulcohasis was obtained from about the same 

 altitude as the Antinous. 



The author wishes to express his thanks and indebtedness to Col. H. H. Godwin- 

 Austen, F.E.S., and Mr. G. K. Gude for assistance rendered him, and also to the 

 Kev. Dr. H. M. Gwatkin for help in interpreting some of the radulae of the several 

 forms here figured. 



The following is a list of the species obtained arranged according to the stations : — 



rXesta citrina (Linn.) *. 



Launch Camp < Cristiffibba toriilabia (hesson). 



^Papuina lituus (Lesson). 



{Cristigibba sp. 

 Papaina luollastoni, sp. n. 

 Melania plumbea Brot. 



* [The parentheses around the names of authors placed after scientific names in this paper are used ia 

 accordance with Article 23 of the International Rules of IS omenolature (Proc. 7th Int. Cong. Boston, 1907, 

 p. 44 (1912).— Ediiob.] 



