G 



the rosfcral shield permits the slender-forked tongue to dart 

 in and out with a rapid quivering motion. On separating 

 the upper and lower jaws, one cannot fail to be struck with 

 the exact fit of these two parts. Every relief on one surface 

 fits into a corresponding depression on the other surface, and 

 accurate apposition of every part is obtained. The roof of 

 the mouth is divided into three parts by the four rows of 

 teeth (Plate II.) These three depressions receive the three 

 prominences of the lower jaw, on each side the mandi- 

 bular teeth, in the middle the windpipe. The prehensile 

 apparatus is thus composed, on each side, of a row of lower 

 teeth fitting between two rows of upper teeth ; the middle 

 space being occupied by the windpipe, or rather its upper 

 extremity, the larynx. This, however, only occupies the 

 two posterior thirds of the middle space, as the anterior 

 third is occupied, above by the nasal fossse the floor of 

 which forms a low fore-palate, below by the sheath of the 

 tongue. The posterior aperture of the nasal fossae is there- 

 fore just in front of the aperture of the larynx (the glottis) 

 and air passes in a straight course from the nostrils to the 

 windpipe. Beneath the skin of the lips, especially at the 

 angle of the upper jaw, are numerous small salivary glands, 

 but their orifices are too small to be detected. 



The salivary glands extend along the dentary portions of 

 both jaws and transude their contents through small orifices 

 within the mucous fold surrounding each tooth.* They are 

 usually four in number on each side, the maxillary, mandi- 

 bular, lacrymal, and nasal, but their size and disposition 

 vary considerably. The latter two supply the palatine and 

 pterygoid teeth with saliva, but the lacrymal, according to 

 Cloquet, furnishes also the small quantity of lubricating 

 fluid required between the eyeball and is epidermal covering. 



Every Indian snake, except the genus Oligodon and some 

 ■^ Such is my impression both from dissection and from analogy. 



