Proceedings of the British Association. 101 



A paper was read by Mr. J. Hogg, on the Ornithology of a por- 

 tion of the North of England, entitled, ' A catalogue of the Birds 

 observed in South-East Durham and North- West Cleveland.' — The 

 author entered into an extended view of the habits of many of the 

 species, and made remarks upon the nomenclature of some of our 

 British authors. He also proposed some modification in the classifi- 

 cation of birds, adopting some of the families of Cuvier as additional 

 tribes, incorporating at the same time with them the greater part of 

 the families adopted by our English ornithologists. The number of 

 species contained in the catalogue amounted to 210. 



The President observed, that as the author had referred to some 

 remarks of his on the willow- wrens, he could state that he believed 

 that there were four British species, two of which were well known, 

 and two more obscure. There was first, the Sylvia trochilus, which 

 breeds on the ground, and builds its nest on heaths, and even in 

 strawberry beds ; secondly, wood-wrens, which were found in 

 woods ; thirdly, the Sylvia rufa, which occurred in his own parish, 

 in Yorkshire ; fourthly a bird called the chifTchaff, but confounded 

 with the last, but which he called the Sylvia loquax. This is very 

 common in Yorkshire. Why they are not distinguished, is, that the 

 young birds have a brighter plumage than the old ones. Another 

 bird mentioned by Mr. Hogg, the whinchat, was frequently called 

 grasschat in Yorkshire, and followed the mowers during haymaking. 

 The godwit had been mentioned ; it had a long bill, and it was ge- 

 nerally supposed that birds with long bills lived by suction ; but 

 this was not the case with the godwit, as it fed voraciously and 

 flourished upon barley. It could not drink in deep water, but 

 was always obliged to have recourse to the edge of a stream to 

 drink. 



Abstract of a paper ' On the Flight of Birds.' By T. Allis. — 

 Birds require the centre of gravity to be placed immediately over the 

 axis of motion for walking, and beneath it when flying ; when sus- 

 pended in the air, their bodies naturally fall into that position which 

 throws the centre of gravity beneath the wings. The axis of motion 

 being situated in a different place in the line of the body when walk- 

 ing, from that which is used when flying, the discrepancy requires to 

 be compensated by some means in all birds, in order to enable them 



