140 Reports and Proceedings — 



graptus MurcJiisoni-zone of the Lower Llandeilo is found. On this 

 horizon are the first traces of volcanic activity : acid lavas and tuffs 

 are here interbedded with the slates. The Middle Llandeilo is partly 

 faulted out in Goodwick Bay, and near Newport is penetrated by 

 huge intrusive sheets of diabase. The Upper Llandeilo is marked 

 near its base by a thick zone of lava-flows, which are overlain 

 by fossiliferous shales. Hartfell graptolites have been found in the 

 overlying grey and black slates. The lavas and breccias on 

 Strumble Head are held to be on the same horizon as those near 

 Newport. 



All the lavas are acid ; some are soda-potash felsites. Nodular, 

 banded, and perlitic structures are sometimes visible. Crypto- 

 crystalline, microlitic, and micropoikilitic types of ground-mass are 

 possessed by these lavas ; the latter type is held to be probably 

 a contact-phenomenon. The intrusive masses consist of diabase, 

 with important tachylitic and variolitic modifications. 



3. " On the Mean Eadial Variation of the Globe." By J. Logan 

 Lobley, Esq., F.G.S. 



The author submits considerations (chiefly derived from the 

 characters of the earlier sediments) which lead him to suppose that 

 crust-folds have not been produced by continuous contraction of the 

 Earth, and that the planetary heat and mean radius of the Earth 

 have been practically invariable during the period which has elapsed 

 since Cambrian times. 



IIL — February 6th, 1895. — Dr. Henry Woodward, F.R.S., 

 President, in the Chair. The following communications were read : — 



1. "On Bones of a Sauropodous Dinosaur from Madagascar." 

 By E. Lydekker, Esq., B.A., F.R.S., V.P.G.S. 



The bones described in the paper were collected by Mr. Last to 

 the east of the town of Narunda, on the north-eastern coast of Mada- 

 gascar. They include vertebrje, limb-bones, and portions of pectoral 

 and pelvic girdles. These bones are described in detail, and the 

 animal which possessed them is referred to the genus Bothrio- 

 spondylus, Owen : a dorsal vertebra, described in the paper, being 

 taken as the type of the new species. 



The identification of the Malagasy reptile with a type occui'ring 

 in the Jurassic rocks of England harmonizes with the reference of 

 some of the strata of the island to the Jurassic period. 



2. " On the Physical Conditions of the Mediterranean Basin 

 which have resulted in a Community of some Species of Fresh-water 

 Fishes in the Nile and the Jordan Waters." By Prof. E. Hull, 

 M.A., LL.D., F.R.S., F.G.S. 



The author summarizes the evidence in favour of the existence 

 of barriers in post-Miocene times, separating the Mediterranean 

 area into a chain of basins. He brings forward arguments in 

 support of his contention that the waters of the eastern (Levantine) 

 basin became fresh during a period when the area of evaporation 

 was smaller, and the supply of river-water greater, than at present. 

 Into this fresh-water lake the waters of the Nile would flow directly. 



