74 PHEASANTS FOB COVERTS AND AVIARIES. 



birds when sitting tte scent which is given out by the animal 

 at other times is suppressed; in proof of this statement is 

 adduced the fact that dogs, even those of the keenest powers 

 of smell, will pass within a few feet, or even a less distance, 

 of a sitting pheasant without evincing the slightest cognizance 

 of her proximity, provided she is concealed from sight. By 

 others this circumstance is denied, they reason a priori that 

 it is impossible for an animal to suppress the secretions and 

 exhalations natural to it — secretion not being a voluntary act. 

 I believe, however, that the peculiar specific odour of the bird 

 is suppressed during incubation, not, however, as a voluntary 

 act, but in a manner which is capable of being accounted for 

 physiologically. The suppression of the scent during incuba- 

 tion is necessary to the safety of the birds, and essential to 

 the continuance of the species. I believe this suppression 

 is due to what may be termed vicarious secretion. In other 

 words, the odoriferous particles which are usually exhaled by 

 the skin are, during such time as the bird is sitting, excreted 

 into the intestinal canal, most probably into the caecum or 

 the cloaca. The proof of this is accessible to everyone ; the 

 excrement of a common fowl or pheasant, when the bird is 

 not sitting, has, when first discharged, no odour akin to the 

 smell of the bird itself. On the other hand, the excrement 

 of a sitting hen has a most remarkable odour of the fowl, 

 but highly intensified. We are all acquainted with this smell 

 as increased by heat during roasting ; and practical poultry 

 keepers must have remarked that the excrement discharged 

 by a hen on leaving the nest has an odour totally unbke 

 that discharged at any other time, involuntarily recalling 

 the smell of a roasted fowl, highly and disagreeably intensified. 

 I believe the explanation of the whole matter to be as follows : 

 the suppression of the natural scent is essential to the safety 

 of the bird during incubation; that at such time vicarious 

 secretion of the odoriferous particles takes place into the 

 intestinal canal, so that the bird becomes scentless, and in 

 this manner her safety and that of her eggs is secured. This 



