52 



Prof. W. K. Parker. 



[Jan. 27, 



and when consequently 



we have 

 and 



C- 



1 = 



(n— l)fi 

 7 Z^i-> 



= r + Rlog (v-v ), 

 TH 2 



TR + ra/*(i;-i; )V 



It would be most important if by some method, Kcenig's for in- 

 stance, or by inserting a small microphone into a tube, the velocity of 

 so and in substances in various states could be accurately determined, 

 as that would enable us to determine C and c separately. 



Iir. " On the Morphology of Birds." By Professor W. K. 

 Parker, F.Pt.S. Keceived January 13, 1887. 



(Abstract.) 



Introductory Remarks. 



During the time that the special study of the development of the 

 skull has occupied my attention, the rest of the skeleton has been 

 neglected ; it has, however, had its cultivators in no small number. 



In a limited degree the skeleton has been worked out by me ; — for 

 instance, the shoulder- girdle and sternum in the Yertebrata generally ; 

 in birds, the whole skeleton did at one time — a quarter of a century 

 ago — take up much of my thought. 



The development of the skeleton, generally in this Class, is a subject 

 of great interest, and I am anxious to catch up all the scattered 

 results that lie before me, of the excellent but extremely limited 

 labours of other biologists. 



I did begin the study of the development of the limbs, sternum, 

 pelvis, and spine, in 1842, and some of the results will be brought 

 forward in the present paper. 



This will be, I trust, but the first-fruits of my most recent work ; 

 for, during the long years that have elapsed since this research was 

 fairly begun, I have lost no opportunity of laying up in store 

 embryos and young of birds of many kinds. These stores, if well 

 worked out, will yield a series of papers like the one now offered to 

 the Society.* 



* Although I have for many years past kept a register of the presents of 



