MOLLUSCA. 



II.-GASTBOPODA. 



By EDGAR A. SMITH, I.S.O. 

 (Plates I. and II.*) 



ALTOGETHER twenty-six species of- Gastropods (exclusive of a few Nudibranchs 

 and some Pteropods) and fourteen Lamellibranchs were obtained by the Expedition, 

 Three-fourths of these appear to be new. The majority of them are small and 

 insignificant, but among the rest are a few striking forms, notably the new genus 

 Trichoconcha, a very remarkable Chiton, the Trophon longstaffi., and a beautifully 

 sculptured Lima. A glance at the collection at once suggests that it was obtained 

 either in deep water or a cold climate, for the almost total absence of colour in 

 nearly every instance is characteristic. It does not show any particular resemblance 

 to the Arctic fauna ; indeed, the majority of the genera have almost a world- wide 

 distribution. The genus Trophon, for instance, although typically a northern and 

 Antarctic group, has a characteristic representative in T. carduelis of Watson, 

 which occurs off Sydney in 410 fathoms; and it will probably eventually be shown 

 that many genera, which are usually regarded as peculiarly Arctic, have a much 

 wider range than has been anticipated, although they may occur at much greater 

 depths than in northern latitudes. Of the previously described species recorded in 

 the following pages nearly all are known from Kerguelen Island, and possibly most 

 of the remainder may also occur there. Only a single species was collected which 

 was obtained by the ' Belgica.' 



NEOBUCCINUM EATONI. 



Buccinopsis eatoni, Smith, Ann. Mag. Nat. Hist., Vol. XVI., 1875, p. 68. 



Neoluccinum eatoni, Smith, Phil. Trans. Koy. Soc., Vol. CLXVIIL, 1879, p. 169, pi. ix., figs. 1, la; 

 Tryon, Man. Conch., Vol. III., pp. 100, 197, pi. Ixxvii., figs. 357, 358; Smith. 'Southern Cross' 

 Mollusca (1902), p. 202 ; Martens, Deutsch. Tiefsee Exped., Vol. VII., p. 63 (1903). 



Six miles N.W. of Hut Point, 180 fathoms. 



A single specimen only was obtained. It is of the same elongate type as those 

 collected by the ' Southern Cross' Expedition at Cape Adare in 7-10 fathoms. 



* For explanation of plates, see Lamellibranchiata, p. 7. 



