292 CLASS IIEPTILIA. 



This conjunctive membrane invests the two anterior thirds 

 of the globe of the eye, to which it adheres closely, and 

 a part of the motive muscles of the organ, as well as the 

 lachrymal gland, whose conduits appear to traverse it behind. 

 In front and below, it is pierced with a hole or rounded pore, 

 with a single lachrymal point, which is continued along 

 with a membranous conduit, very slender and transparent. 

 This last is engaged in an infundibuliform aperture, which 

 the OS unguis presents to it, passes into the external paries 

 of the nasal fosses, and opens at the exterior part of a large 

 anfractuous pouch, which receives the tears and transmits 

 them into the mouth. 



As for the lachrymal gland, the existence of which in the 

 ophidians has been generally denied, until latterly, it is 

 voluminous in many species, and lodged in the orbit behind 

 the globe of the eye. Its form is triangular. Its external 

 face is covered by the skin, which adheres to it but little. 

 The anterior face sends slender and transparent threads to 

 the conjunctive membrane, which appear to be' the excretory 

 conduits of the organ. It is enveloped by a cellular mem- 

 brane, very slender, and composed of a multitude of rounded 

 granulations, whitish, tolerably voluminous, and vmited 

 together by means of vessels and nerves which penetrate it 

 through its external face. 



In the majority of serpents with venomous fangs, the vise 

 lachrymales exhibit a remarkable modification, inasmuch 

 as the lachrymal canals, immediately pour the tears iirto the 

 nasal fosses, without depositing them in the sac or inter- 

 maxillary reservoir which we have described. 



In all of them, generally, in spite of the existence of the 

 fluid secreted by the apparatus in question, the eye, other- 

 wise constantly fixed, is always dry at its surface. 



As well as the other reptiles, the ophidians have an 

 organ of hearing, composed of a vestibulary sac, a vestige 



