370 SECTIONAL TRANSACTIONS.— D, E. 



Prof. L. P. W. Renouf. — Photos, &c., of Fauna of Lough Flyne. 



Rev. Brade Birks." — British Chilopod and Diplopod Fauna. 



For the purpose of this exhibit, the main subdivisions of the two classes are those 

 given in the articles ' Centipede ' and ' Millipede ' by R. I. Pocock, F.R.8., Encyclo- 

 paedia Britannica, 1910, Vol. V., pp. 669-674, and 1911, Vol. XVIII., pp. 468-475. 

 Some bionomic, distributional, and diagnostic particulars are indicated. 



Prof. E. B. PouLTON. — Mimicry in the forms of ' Papilio dardanus.' 



Dr. PiXELL Goodrich. — Phagocytosis in Gammarus. 



Dr. T. S. P. Strangeways and Dr. H. B. Fell.— Differentiation in 

 vitro. 



Dr. J. G. Thomson. — Fish Coccidia recently described as Intestinal 

 Parasites in Man. 



Dr. G. D. Hale Carpenter. — Specimens of Butterflies of the genus 

 Pseudacrsea and map of distribution. 



Mr. Scott. — Photographs of eminent American and other Biologists. 

 SECTION E.— GEOGRAPHY. 



(For references to the publication elsewhere of communications entered in the 

 following list of Transactions, see page 446.) 



Thursday, August 5. 



1. Mr. H. 0. Beckit.— T^e Site and Groivth of Oxford. 



Evidence of occupation by prehistoric man on or close to the present site of the 

 city exists, but the rise to importance as a centre of settlement of what is now known 

 as Oxford does not seem to be very ancient. 



Topographically the site is determined by the occurrence, near the confluence of 

 the rivers Thames and Cherwell, of patches of river gravel rising above the flat alluvial 

 floors of valleys traversed in braided channels, and very inadequately drained, by 

 these two streams. Only towards the north, along a staircase of these older valley 

 deposits, now isolated as terraces, i.e. just where the largest extension of the modem 

 town has occurred, is it possible to leave Oxford without crossing one or other of these 

 belts of damp and periodically flooded bottom land. On three sides, therefore, the 

 eite is relatively defensible, but the building of roads — to east and west and south — 

 is a matter of some difficulty ; even to-day made roads in the Oxford district run for 

 the shortest possible distances on alluvial ground. Where practicable the older 

 tracks avoid also the bare clays. 



Passing to wider geographical relations, it is to be noted how Oxford lies in a 

 critical, transitional position in the entrance to a gap in the scarpland of the Oxford 

 Heights, which has to be climbed by all roads except those to the north and that branch 

 of the western road which finds easy passage through the lateral Botley Gap. None 

 of the roads now radiatmg from Oxford belongs originally to a planned system of 

 general communication : all represent gradual improvements of local roads or track- 

 ways. Oxford lies off even the side-roads of the Roman period, and it is to be presumed 

 was of no importance in Romano-British times. 



It is possible, however, to trace the development of the city from Domesdaj' 

 Book and beyond, and to find in that growth some significant environmental influences, 

 such as (1) the cramped area of the peninsular gravel terraces, beyond the limits of 

 which the houses of the town have stretched only quite recently, and (2) a growing 

 nodality discernible in increasing measure as first river navigation, and later on canal, 

 metalled road, and rail, linked up larger and larger areas of the south-eastern English 

 lowland about a notably convenient centre for communications. Oxford lies sufficiently 

 removed from London to dominate the surrounding territory, like itself non-industrial. 

 Favoured by position, and still more by its fame among the schools, it has grown from 

 one of many Thames-side towns, mostly markets or road stations, into a city of nearly. 



