STRAY FEATHERS. 



Vol. VIII. APRIL 1879 No 1. 



With /our plates. 



By R. Lydekkbr, B.A., Geological Survey of India. 



Preface. 



I HAVE been asked by Mr. Hume to contribute to '' Stray 

 Pbathers'^ an elementary sketch of the general osteology of 

 birds, in order that ornithologists in India, who have no oppor- 

 tunity of obtaining works devoted specially to that subject, may 

 thereby be able to arrive at a general idea of the structure and 

 homologies of the bird-skeleton. 



Many ornithologists content themselves merely with a know- 

 ledge of the external parts of birds, and remain entirely un- 

 acquainted with the internal anatomy. As far as regards the 

 distinction between closely-allied species of birds, this superficial 

 knowledge is probably in most cases suflScient^ because the 

 variations in the internal anatomy of most allied groups of 

 birds are in general very small. When, however, the naturalist 

 desires to compare the relationships of more distantly-related 

 avian groups, he will not be able to arrive at a truthful conclu- 

 sion, unless he be acquainted, at least to some extent, with their 

 internal as well as their external structure. The present sketch 

 does not pretend to go into any details regarding the osteological 

 anatomy of the various groups of birds, but is merely intended 

 to enable the student to determine for himself the names and 

 homologies of the bones of any birds which he may come across. 

 With this knowledge, the student will be perfectly able to insti- 

 tute for himself comparisons between the homologous bones of 

 different birds, and to draw his own conclusions as to their 

 relationships, as thereby indicated. 



Before reading this sketch I would strongly recommend the 

 reader to obtain for himself the skeleton of any common bird, 

 such as a crow or a kite (which he can easily prepare by macer- 

 ating the body of such bird, or by placing it over an ants' nest,) 



