10 



DR. J. MURIE ON CYGNUS BUCCINATOR. [Jail. 10, 



that two other skins of the same species examined by him afforded 

 smaller dimensions. 



Secondly. — Respecting the osteological evidence afforded by the 

 sternum, it may be stated that both the dead birds exhibit a differ- 

 ence in the shape and relative height of the elevated bony lamella 

 enclosing the convolution of the trachea, likewise in the general di- 

 mensions of the entire sternum, as also in its outline figure when 

 viewed from the inside including the posterior sinuses ; moreover 

 the osseous rings of the trachea, previous to entering the carina, are 

 not the same in each specimen. These marks of variation, whatever 

 their value, may require a separate description. I shall first mention, 

 for the benefit of other inquirers, that the entire skeleton of the one 

 bird is now deposited in the British Museum, at present beside the 

 stuffed specimens of the genus Cygnus ; the sternum of the other 

 f'uiuis part of the osteological series in the Museum of the Royal 

 College of Surgeons. 



The accompanying figures represent these two sterna seen from 



Fis. I. 



Fig. 2. 



Sterna of Truiiipeter Swans. 



above (or inside), but without the trachea and distended bronchise, 

 which are preserved intact in both the original specimens. 



The specimen represented in fig. 1 is the sternum of the male bird 



