72 NATURAL HISTORY 



be suffocated, though both their mouths and nostrils 

 were stopped. This curious formation of the head may 

 be of singular service to beasts of chase, by affording 

 them free respiration: and no doubt these additional 

 nostrils are thrown open when they are hard run 1 . 



1 In answer to this account, Mr. Pennant sent me the following curious 

 and pertinent reply. " I was much surprised to find in the antelope 

 something analogous to what you mention as so remarkable in deer. 

 This animal also has a long slit beneath each eye, which can be opened 

 and shut at pleasure. On holding an orange to one, the creature made 

 as much use of those orifices as of his nostrils, applying them to the fruit, 

 and seeming to smell it through them." 



[The structure of the glandular cavities, of which the orifices are here 

 alluded to, precludes the possibility of their ever being used as accessory 

 respiratory passages, or organs of scent. 



The common integument is continued over the margins of the orifice, and 

 is reflected over the whole of the interior of the cavity, which is altogether 

 imperforate, except by the ducts of a large flattened mucous gland, which 

 occupies its base ; a few short hairs spring up in the interspaces of the 

 terminal orifices of the ducts. Mr. Hunter, whose attention was probably 

 called by his friend Pennant to this peculiarity of the deer and antelopes, 

 has left several preparations of the glands and sinus, taken from the 

 Indian and another species of antelope, and also from the deer: in which 

 their condition as tegumentary sacs, having no communication with the 

 nose, is clearly shown. 



Conceiving that the secretion of these glands, when rubbed upon 

 projecting bodies, might serve to direct individuals of the same species to 

 each other, I prepared a tabular view of the relations between the habits 

 and habitats of the several species of antelopes, and their suborbital, 

 maxillary, post-auditory, and inguinal glands, in order to be able to com- 

 pare the presence and degrees of development of the glands, with the 

 gregarious and other habits of the antelope tribe. 



From this table it was, however, evident, that there is no relation 

 between the gregarious habits of the antelopes which frequent the plains 

 and the presence of the suborbital and maxillary sinuses ; since these, 

 besides being altogether wanting in some of the gregarious species, 

 are present in many of the solitary frequenters of rocky mountainous 

 districts. The supposition, therefore, that the secretion might serve, 

 when left on shrubs or stones, to guide a straggler to the general herd, 

 falls to the ground. 



The secretion of those cutaneous glands which are designed to attract 

 the sexes, is generally observed to acquire towards the reproductive 

 period a strong musky odour, as in the elephant and alligator, but the 

 secretion of the suborbital sinuses, even when these are most fully 

 developed, is devoid of any approach to a musky, or any other well defined 

 odour. 



Nevertheless, the subjoined observations of Mr. Bennett tend to give 



