ShUFKLD T : OSTF.OLOOY OV I UK HkRODIONES. 



185 



So far as I have examined, this is the method of decussation in each 

 instance, i. e., the right hand groove being the one that passes over 

 the superior manubrial surface. 



It is just possible that this crossing of the coracoids may have arisen 

 in the habit of the ancestors of the present Herons, of passing con- 

 stantly through very narrow places, as dense cane-brakes, or such 

 other growths of analogous character, where they probably resorted 



Fig. II. Left lateral view of tlie fiircula of Ardca herodias. 



Fig. 12. The same bone from in front. Natural size, and from the same skeleton 

 as shown in figures 8, 9, and 10 and others. 



and spent the major part of their time. There would undoubtedly 

 be an effort made many times a day to compress the body and 

 diminish its general bulk in a transverse direction, in such situations. 

 Moreover, the coracoids (if arranged as in most birds) would consti- 

 tute the principal obstruction to such comjiression ; and it certainly 

 lessens the width of the bird's body to have them crossed as they are 

 in the Herons. If we commence sufficiently early in the life of the 

 individual, bones and the normal position of bones may be altered 



