Reports and Proceedings— Geological Society of London. 563 



A. equintim, occurs. This form fairly closely resembles the European 

 species, A. aurelianense, but in some respects is of a more modernised 

 type. The affinities of the genus are discussed at length and cogent 

 reasons given for considering that it is quite off the direct line of 

 descent of Equus, being probably an abortive side branch derived 

 from Miohippus, or some allied form. If this be true the European 

 representatives of the genus must have reached the Old World by 

 migration. 



The KhinoceridEe are represented in the lower beds by some 

 undeterminable fragments only, but in the upper the remains of a 

 species of Aphelops are found. The author points out an inter- 

 esting series of parallelisms in development between the hornless 

 Rhinoceroses of America and their horned congeners of the Old 

 World ; the common ancestors of the two groups are probably to be 

 found among the Aceratheria of the Oligocene. 



Of the Artiodactyla, several species of Oreodonts referred to the 

 genera Mesoreodon, Merychyus, Merycochoerus, and Cyclopidius, are 

 described. Mesoreod.on chelonyx is peculiar from the fact that it 

 possesses an ossified thyroid cartilage, a character unique among 

 mammals. It is suggested that this structure, like the greatly 

 expanded basihyal in the howling Monkeys, was connected with 

 great power of voice. The same species is further remarkable for 

 the presence of a small ossified clavicle and of a distinct meta- 

 cromial process on the scapula. 



A small species of Blastomeryx, B. antelopiniis, is described and its 

 affinities considered. It appears to be an Old World type, nearly 

 related to Palceomeryx, and may possibly be an ancestral form of 

 Antilocapra, the American Prong-horn Antelope, which it must 

 have closely resembled in outward form, the horns, however, being 

 unbranched. 



The Camelidae are represented in the lower beds by PoehrotTierium, 

 and in the upper by Protolahis and Procamelus. In the axis 

 vertebra of Protolahis the odontoid process is intermediate in 

 structure between the peg-like form occurring in Poehrotherium and 

 the spout-like condition found in Procamelus and the recent Camels, 

 this latter form having been acquired among the Camels by precisely 

 the same series of modifications as in the Equidte, in which series 

 Miohippus, in this respect, represents Protolahis. 



Finally, in the upper beds remains of a Mastodon, M. proavus, 

 Cope, are fouijd ; this is the earliest occurrence of the genus in 

 America. 



I2,:b:pos,ts j^.i<tjd I^I^OG:E]JEIDII^^C3-S- 



Geological Society of London. 



November 7th, 1894:. — Dr. Henry Woodward, F.E.S., President, 

 in the Chair. 



Sir John Lubbock exhibited specimens of fossiliferous limestone 

 from the valley of Lauterbrunnen, at Miirren. He pointed out that 

 the specimens contain Nummulites Bamondi, Orbitoides dispansus, etc. 



