564 Geological Society : — 



diate antecedent is heavy rainfall concentrated over a portion of the 

 Bay, accompanied by strong indraught, most marked from the Indian 

 Ocean at the entrance of the Bay. This indraught from the Indian 

 Ocean gives rise to strong winds and heavy rain at the stations on 

 the south and west coasts of Ceylon." 



" The air-motion in cyclones is one of indraught ; and therefore 

 the wind-direction at any point is not at right angles to the direction 

 of the centre. The stream-lines or the lines of air-motion are 

 spiral curves. The relation between the wind-direction and the 

 direction of the centre is probably not invariable, but depends on 

 the intensity of the storm or the baric gradient. The law as laid down 

 by Mr. Wilson in the report of the Midnapore cyclone is probably 

 the nearest approximation. With the face to the wind, the direction 

 of the centre is from ten to eleven points to the right-hand side." 



LXVIII. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



[Continued from p. 421.] 



June 11, 1879.— Prof. Joseph Prestwieh, M.A., F.R.S., Vice- 

 President, in the Chair. 



^HE following communications were read : — 

 -*• 1. " On a Mammaliferous Deposit at Barrington, near Cam- 

 bridge." By the Bev. 0. Fisher, M.A., F.G.S. 



2. " Further Discoveries in the Cress well Caves." Bv Prof. 

 Boyd Dawkins, M.A., F.B.S., F.G.S., and the Bev. J. M. Mello, 

 M.A., F.G.S., with notes on the Mammalia by the former. 



3. " On the Pre-Cambrian Bocks of Shropshire." Part 1 . By 

 C. Callaway, Esq., D.Sc. Bond., F.G.S. 



The author commenced by describing the physical geography of 

 the ridges intervening between the vicinity of Wellington and the 

 Longmynds, viz. Lilleshall Hill, the Wrekin, and the chain of the 

 Caradoc Hills. He passed on to describe the stratigraphy. At 

 Lilleshall are slaty beds dipping about JN T .N.W., and a rhyolitic 

 agglomerate ; at the N. end of the Wrekin a granitoid soil, pro- 

 bably of clastic origin, with a mass of decomposed intrusive rhyolite. 

 The Wrekin consists of rhyolitic agglomerates, with (probably) lava- 

 flows and a few basalt dykes, the general dip of the bedded rocks 

 being to the N. At the southern end (Primrose Hill) granitoid 

 gneisses (some closely resembling the hornblendic gneiss of Malvern) 

 occur. In the Caradoc range intrusive greenstones are more largely 

 developed ; but here also are bedded Pre-Cambrian rocks. Other 

 smaller exposures in this vicinity were also described. The prevalent 

 strike over the whole district is about E.KE.-W.S.W. The evi- 

 dence of their age is often very clear, as they are overlain (with 

 marked unconformity) by quartzites (sometimes containing rhyolitic 

 fragments) which are clearly much older than the Hollybush Sand- 

 stones. 



