1889.] ON THE ANATOMY OF POLYBOROIDES. 11 



With the evidence now before us there is no longer ' any reason 

 to doubt that the skeleton described by Gervais really belongs to 

 Trichys. He gives as the numbers of vertebrae : — D. 16, L. 5, S. 4, 

 C. 21, whilst I find in our skeleton D. 16, L. 6, S. 3, C. 24. The 

 caudal vertebral column bears four compressed, hatchet-shaped 

 chevron-bones between the fourth and eight caudal vertebrae. The 

 eighth vertebra marks the boundary between the proximal and 

 distal portions of the caudal series, differing much in shape from the 

 seventh as well as the ninth, and having the transverse process 

 dilated into a broad lamina extending along the whole length of the 

 centrum. The seven vertebrae preceding it are provided with 

 strong and long lamelliform transverse processes, whilst the apo- 

 physes rapidly disappear from the ninth vertebra backwards. 



P.S. — Through the kindness of Dr. Jentink I have been able to 

 examine one of the specimens described by Waterhouse as Atherura 

 fasciculattt, and find that I was right in supposing that they are 

 identical with Trichys. I have to add that Dr. Jentink adopts 

 now AVaterhouse's identification, an opinion which, for reasons stated, 

 I do not share. Dr. Jentink also informs me that the specimens 

 in the Leyden Museum come from Malacca, not from Siam. — 

 March 1 \th. 



i\ 



6. On certain Points in the Anatomy of the Accipitres, 

 with reference to the Affinities of Polyboroides. By 

 Frank E. Beddard, M.A.^ Prosector to the Society. 



[Eeceived February 19, 1889.] 



I have recently had the opportunity of dissecting a specimen of 

 Polyboroides which died in the Society's Gardens ; the specimen was 

 deposited by Lord Lilford, who expressed a wish that the skin should 

 go to the British Museum ; after the bird was skinned it was still 

 possible to examine into the arrangement of certain of the muscles 

 and of other organs, which examination has, in my opinion, thrown 

 some light upon the affinities of the bird. For this reason I think 

 it worth while to publish the notes of my dissection, although this 

 paper is necessarily very far from containing a complete account of the 

 anatomy of Polyboroides. 



I have not attempted to give any description of its osteology, 

 which has been lately worked out in detail by Prof. ^lilne-Edwards", 

 but in a different species, P. radiatus. This account shows that the 

 supposed resemblances oi Polyboroides to Serpentarius are purely 

 superficial, and that in reahty it comes nearest to the Buzzards. The 

 position assigned to the genus by Sharpe^ (in the subfamily Accipi- 



1 Proc. Zool. Soc. 1876, p. 712. 



^ Milne-Edwards aud Grandidier, Hist. phys. nat. et polit, de Madagascar : 

 Oiseaux, torn. i. p. 50. 



' B. M. Catalogue of Birds, vol. i. p. 47. 



