418 



ANIMAL MECHANICS. 



The last example that 1 shall give of the theory of mus- 

 cular types, is the remarkable case of the wings of birds, 

 which, for many reasons, is to be considered in detail. 



The development of the great pectoral in birds has, of 

 course, been noticed by every anatomist ; but the theory of 

 muscular types enables us to present it to the eye in a manner 

 that admits of immediate comparison with the corresponding 

 muscle in other animals ; and to demonstrate the impossibility 

 of flight, in other animals not endowed with the peculiar mus- 

 cular type of birds. 



The birds from which I have made my measurements are 

 the following : — 



1. Albatross (two examples, measuring, respectively, 

 from tip to tip of extended wings, i i ft. o in. and 9 ft. 3 in.). 



2. Common Swan. 



3. Dorking Cock. 



4. Aylesbury Duck (two examples). 



5. Gannet. 



6. Curassow. 



7. Jabiru (two examples). 



8. Stork (two examples). 



9. Common Heron. 



10. Squacco Heron. 



11. Flamingo. 



12. White-Headed Eagle (two examples). 



13. Grebe. 



14. African Parrot. 



15. Peregrine Falcon. 



16. White Crane. 



17. New Zealand Weka Rail (two examples). 



