462 Transactions. 



All of these genera, however, have now been found in rocks admitted to 

 be of Miocene age. 



In general it appears that, apart from purely littoral forms, of which 

 we have comparatively few fossils, there have been no important generic 

 additions to our molluscan fauna since early Tertiary times. The collection 

 of over two hundred species from the small bed at Target Gully suggests 

 that mollusca were more abundant in New Zealand waters in this Miocene 

 period than at the present time, and that generically the fauna was much 

 richer. 



Specimens of some seventy-five of the Target Gully species were sent 

 to M. Maurice Cossmann, the distinguished palaeoconchologist, of Paris. He 

 has been good enough to examine the shells, and has forwarded the following 

 notes :• — 



" Limopsis aurita (non Brocchi), elle est plus trigone, plus gouflee, la 

 charniere est plus epaisse avec les dents plus grosses. II faut reprendre le 

 nom zealandica Hutton. 



" Cytherea meridionalis aucun rapport avec Chione meridionalis du 

 Pliocene, il faut reprendre le nom vellicata Hutton. 



" Chione oblonga de Target Gully est egalement differente de C. oblonga 

 Hanley, du Pliocene ; je propose C. suboblonga Cossm. 



'' Chione mesodesma de Target Gully n'a de menie aucune analogie de 

 forme, d' ornamentation ni de charniere avec celle du Pliocene, je propose 

 done C. marshalli Cossm. 



" Ces trois especes sont du reste des Ventricoloidea Sacco (v. le vol. i 

 de ma Conchol. neog. de VAquitaine). 



" Turbonilla oamarutica probablement Acissella. 



" Latirus acuticingulatus et L. compactus sont des Tritonidea. 



" Latirus brevirostris probablement Leucozonia ou un nouveau genre. 



" Mangilia canaliculata est un Ptychatr actus. 



" Mangilia nodosolirata est une Bela (Buchozia). 



" Les deux Cylichnella sont des Bullinella. 



" Leptothyra fluctuate est un Tibumus. 



" Admete praecursoria est un Actaeon." 



A copy of these notes was sent to Mr. Suter, who in reply wrote to me 

 as follows : ' With regard to Cytherea oblonga and Chione meridionalis and 

 C. mesodesma I do not agree with Cossmann." It is thus evident that a 

 good deal of latitude must be allowed for personal opinion, and a corre- 

 sponding difference in the percentage of Recent species in a collection 

 classified by two different authorities. 



The following general remark is made by M. Cossmann about the Target 

 Gully bed : ' Le gisement de Target Gully, pres Oamaru, me semble bien 

 se rapporter a l'epoque miocenique, et je crois que les especes de le niveau 

 sont bien distinctes de celles des mers actuelles aussi bien que de Pliocene. 

 Aucune ne m'a semble pareille a celles du Miocene d'Australie que je 

 possede/' 



M. Cossmann makes frequent reference to the replacing of Lamarck's 

 names by those of Bolten, and maintains that this is unnecessary and 

 inadvisable. Whi'e fully sympathizing with him in this view, it is advis- 

 able in this country to use Bolten's names so far as Recent genera are 

 concerned as they have been adopted, in Suter's Manual of the New 

 Zealand Mollusca. 



