0««* PREFACE 



The Author of the following work does not by any means intend to present it to the public as 

 a perfect work on the Osteology of Birds, but as a mere sketch on which other works or 

 descriptions of birds may be founded. The information contained in it is much more extensive 

 than has been published in any work on the subject before ; and it is the Author's intention to 

 supply deficiencies, when he obtains any varieties to describe, and to figure any new species or 

 better specimens, in the form of an Appendix. Until a larger collection of the skeletons of birds 

 is got together, it is almost impossible to comprehend the characters of each Order, Family or 

 Sub-Family, or genus. The characters derived from the head, sternum, pelvis, and leg-bones, 

 are most reliable. A character of great value may also be derived from the numbering of the 

 vertebras and ribs ; but although I have taken great pains to get the numbers as correct as 

 possible, I am convinced myself that some mistakes will be found, — chiefly in the sacral 

 vertebree, which cannot be counted accurately without a section of the pelvis. The anterior 

 short ribs are all counted as false; all those, whether they are articulated to the pelvis or no, 

 so that they are connected with the sternum, are called true. It has been stated that birds do 

 not differ so much in the skeletons as to make osteological characters of any use ; this, although 

 in many instances I agree with the arrangements made from external character, is certainly not 

 the case. Birds differ quite as much as mammalia or reptiles in their osteological characters ; 

 but those characters are much more difficult to detect, in consequence of such general similarity 

 of form. 



Measurements also give valuable characters. In this work the breadth of the sternum 

 is taken at its widest part anterior to the ribs, and behind them ; the length of the pelvis 

 is taken from the anterior edge to the end of the os pubis, and the breadth at the widest 

 part. 



The Plates illustrating this work have been executed in zincograph by Mr. Erxleben ; 

 and I beg here to thank him for the trouble he has taken over them. They have been printed 

 by Messrs. Day & Co. (now, I believe, made a limited company), and, except some mistakes in 

 the numbering, have been carefully executed. 



