40S Proceedings of the Zoological Society of London : [April 



ation of its relative development in the several Indian Antelopes of the 

 Society's Menagerie. 



In the more aged of these individuals, as indeed in the adult Indian 

 Antelope generally, the large cutaneous follicle heneath the eye,. known 

 as the lacrymal sinus, is so prominent as to form a most striking c 

 in the animal's physiognomy : it never appears as a simple slit, its 

 thickened edges pouting so widely as to be at all times partially evert- 

 ed. When the animal is excited, and it is constantly highly excitable, 

 the eversion of the bag becomes complete, and its thick lips being 

 thrown widely back, the intervening space is actually forced forwards 

 so as to form a projection instead of a hollow : the animal is, on such 

 occasions, delighted to thrust repeatedly the naked lining of the sac 

 against any substance that is offered to him, which soon becomes load- 

 ed with the odour that has been referred to as belonging to the secre- 

 tion. In the second individual, although it is perfectly mature, the 

 protrusion of the inner surface of the sac is not quite to so great an 

 extent as in the more aged male ; and the less thickened edges of the 

 sinus allow of a nearer approximation to its closure in the unexcited 

 state of the animal. The youngest male has the lips of the sinus small 

 and closely applied to each other, 5 j as to hide completely the whole of 

 the internal lining of the sac, and to exhibit, externally, a mere fissure : 

 in it the lips are but slightly moved when the animal is interested. The 

 emasculated individual, notwithstanding its full growth, has its subor- 

 bital sinus, nearly in the same condition as that of the immature male : 

 it is merely a slight fissure, the edges of which are closely applied to 

 each other ; and in it those edges do not appear to be at all moved, the 

 animal being generally careless and inanimate. It would consequent- 

 ly seem that the same cause which induced the retention, by this in- 

 dividual, of its immature colours, and which arrested the perfect growth 

 of its horns, was adequate also for the checking of the development of 

 the suborbital sinuses. Those organs, therefore, would appear to be 

 dependent on sexual perfection ; and consequently to be, in some man- 

 ner yet to be ascertained, subservient to sexual purposes, with the capa- 

 city for which they are evidently, in the phases of their development, 

 essentially connected. 



Mr. Owen, who had conceived it possible that the secretion of these 

 glands, when rubbed upon projecting bodies, might serve to direct in- 

 dividuals of the same species to each other, remarked that he had en- 

 deavoured to test the probability of this supposition by preparing a 

 tabular view of the relations between the habits and habitats of the 

 several species of Antelope, and their suborbital, maxillary, post-auditory, 

 and inguinal glands ; in order to be able to compare the presence and 

 degrees of development of these glands with the gregarious and other 



