Geological Society of London. 383 



Billings, and ArcJiCBOcyatJius, Bill., though ranged with the Eecep- 

 taculitidee by some authors, were shown to have no structural rela- 

 tionship to that family. 



12. " On the Pliocene Mammalian Fauna of the Val d'Arno." By 

 Dr. C. J. Forsyth-Major. Communicated by W. Boyd Dawkins. 



A list of the fossil Mammalia was given, containing the names of 

 thirty-nine species known to the author. This list contains no 

 species common to the older fauna on the limit between Miocene 

 and Pliocene, a fauna characterized by the presence of Hipparion and 

 met with at Pikermi, Eppelsheim, and other places. The Mont- 

 pellier fauna contains an admixture of older and newer types ; but it 

 is not clear that this admixture has not taken place after extraction. 

 Some Val d'Arno types extend to the Sewaliks of Northern India, 

 for Equus Stenonis and Siis Strozzii of the former are probably the 

 same as E. sivalensis and Sus giganteus of the latter. 



]t has been asserted that the marine Pliocene of Italy is older than 

 the lacustrine strata of the Arno valley. This, however, is not the 

 case ; some of the mammalian species found in the latter occur also 

 in shore-deposits belonging to the first named. 



The Pleistocene fauna in Italy appears to be quite distinct speci- 

 fically from the Pliocene. Portions of both, however (often desig- 

 nated the African division), appear to be closely allied. This is 

 especially the case with certain forms of Hycena, Felis, BJiinoceros, 

 and Hippopotamus. Some of the differences between species of the 

 two last-named genera were discussed. 



The relations of the Arno-valley fauna to living Mammalia were 

 next considered, and it was shown that although some genera, as 

 Hippopotamus, are only met with living in the Ethiopian region, a 

 much larger number of forms, such as Tapirus and several bovine 

 and cervine species, are now represented in south-eastern Asia and 

 the Sunda islands. The occurrence of these animals in tropical 

 countries at the present day does not, however, necessarily imply 

 a tropical climate in Pliocene Italy. Some instances in modern 

 geographical distribution are quoted in illustration of this opinion. 

 It is probable that the Pliocene fauna of Europe extended as far 

 as Celebes, and has been preserved in the Indian archipelago by 

 isolation. 



In conclusion it was shown that the preservation of a Miocene 

 form, Myolagus sardonis, in the Pleistocene bone-breccias of Corsica 

 and Sardinia, and the occurrence of Elephas meridionalis and Mastodon 

 arvernensis in beds of different age on opposite sides of the Alps, are 

 instances in support of the view that a single mammalian species or 

 even a few species cannot be sufficient to determine the age of beds. 



In a note appended to the paper. Prof. Boyd Dawkins contested 

 the opinion that no species pass from Miocene to Pleistocene beds, 

 especially in the case of Hippopotamus major of the former and H. 

 ampliihius of the latter. 



13. '^ Notes on the Geology and Mineralogy of Madagascar." By 

 Dr. G. W. Parker. Communicated by F. W. Eudler, Esq., F.G.S. 



This paper commenced with a sketch of the physical geography of 



