120 MR. W. A. FORBES ON BIRDS [Feb. 5, 



the essence of which is " impressibility," and may be described as 

 a more or less complex arrangement for carrying about, nourishing, 

 and propagating a plexus of sensations. 



The two initial questions may then, in conclusion, be answered as 

 follows : — 



( 1 ) Vertebrate limbs are differentiations of continuous lateral folds. 

 They are therefore not limited to four, and are for locomotive conve- 

 nience. There might apparently be several successive paired limbs on 

 each side, just as there are often several successive dorsal fins paired ; 

 and azygos fins and limbs being of the same nature, each separate 

 part may be called a pterygium, and for the sum total of the whole 

 the term sympterygium may be employed. 



(2) Piscine limbs are related to digit-bearing limbs as structures which 

 have diverged less from the primitive condition, a natural consequence 

 of fishes making use of their fins in that medium in which the primi- 

 tive continuous lateral folds were first developed. 



This paper will be puplished entire in the Society's Transactions. 



The following papers were read : — 



1. Reports on the Collections of Birds made during the 

 Voyage of H.M.S. ' Challenger/— No. VII. On the 

 Birds of Cape York and the neighbouring Islands (Raine, 

 Wednesday, and Booby Islands). By W. A. Forbes, 

 F.Z.S. 



[Received December 18, 1877.] 



The collection of Birds made by H.M.S. * Challenger ' at Cape 

 York and in its neighbourhood, of which the following is an account, 

 comprises 61 skins, referable to 37 species. As might have been 

 expected, all, or nearly all, belong to well known Australian forms, 

 one or two only being left uncertain for want of more materials and 

 on account of the immature condition of the specimens. Most of 

 the skins are in excellent condition ; and their value is much increased 

 by the notes in Mr. Murray's journal as to the colour of the soft 

 parts &c. Besides Cape York, Raine Island (at the end of the 

 Barrier Reef), Wednesday Island (in Torres Straits), and Booby 

 Island (also in Torres Straits) were visited, and collections made. I 

 copy the following extracts from Mr. Murray's journal as regards 

 the localities where birds were obtained : — 



" Raine Island, Barrier Reef, Australia. Ship landed two boats 

 for nearly three hours. The following birds were taken " (several 

 sea-birds, Rallus pectoralis, and Strepsilas interpres). 



" Cape York, Somerset. Ship arrived on evening of 1st Sept., 

 18/4 ; left Cape York on Sept. 8th." (44 skins were obtained here). 



"Wednesday Island, Torres Straits. Parties landed the same 

 day (Sept. 8). Most of the birds seen were the same as those shot 



