HABITS OF HOATZIN 



That is just what might be expected of an isolated type 

 like the hoatzin, which seems to be a vestige of a for- 

 merly existing group. That it has been called " rep- 

 tilian " by that distinguished authority upon bird 

 anatomy, the late Professor Parker, F.R.S., is another 

 way of expressing what are undoubtedly inferences to be 

 drawn from its structure. An unpleasant but still 

 accurate name for this South American bird is " stink 

 Pheasant." It derives its characteristic and formidable 

 odour from the berries of a certain shrub upon which it 

 largely feeds. It builds upon these or other shrubs in 

 suitable localities through the northern part of the 

 South American continent. These shrubs overlook 

 water, in which the hoatzin, both young and adult, is an 

 expert swimmer. This is not so extraordinary as might 

 appear. The saying of the hen with her foster ducklings 

 is not by any means so neat a contrast between diver- 

 gent habits of life as has been imagined. Professor 

 Lloyd Morgan has found that a newly-hatched chick of 

 the fowl will swim, and that in a regular and " hand- 

 over-hand " fashion, not to be compared to a confused 

 struggle for existence in an unexpected medium. Phea- 

 sant-like though it is (but here it is perhaps expedient to 

 bear in mind the " dash " of rail), the hoatzin will swim 

 and dive as one to the manner born. The hoatzin 

 possesses at least two unique peculiarities of internal 

 structure. Most birds all except the struthious birds 

 and a very few others possess a deep " keel " to the 

 sternum or breast bone, associated with the attachment 

 of the enormous pectoral muscles, which pull down the 

 wing in flight. In the hoatzin this keel, instead of fading 

 away posteriorly as is common among birds, is deficient 

 anteriorly, and this deficiency of keel is furthermore 

 associated with, or any at rate combined with, a huge 

 and baggy and muscular crop which rests upon this part 

 of the sternum, and the whole upon the branch of the 



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