THE GLOTTIS. 139 



somewhat in the form of a parrot's tongue, is supplied with 

 space in the roof, arched to fit it, the palate teeth enclosing it 

 on each side, w^hile the opening, or glottis, exactly meets the 

 nostrils, les arrieres 7tez, bringing it into communication with 

 the outer air. 



In a little Coluber, just dead, I again had an oppor- 

 tunity of making observations. The membranous coating 

 was so thin and transparent that the rings of the windpipe 

 could be very distinctly traced from a quite forward position 

 in the mouth, and beginning on and over the tongue sheath. 

 The surrounding skin or membrane was also loose and 

 abundant, so that with the point of a needle the upper part 

 of the windpipe could be easily drawn forward beyond the 

 lips. In life the little snake could thus have voluntarily 

 protruded it as occasion required. 



Another day the large reticulated python seemed to 

 intentionally gratify my curiosity by affording me a most 

 leisurely and excellent opportunity for observation. His 

 head was raised, and so close to the glass that the process 

 of swallowing could be watched conveniently. The final 

 swallow, or successive efforts at the last were, as usual, 

 attended with frequent yawns. The glottis, as could on 

 these occasions be distinctly seen, was repeatedly opened 

 and closed, and after being extended beyond the mouth, it 

 gradually resumed its natural position. While the prey 

 occupied the entire space between the gaping jaws, one 

 could see the air-tube pushed forward be7ieath ; but as by 

 degrees the duck disappeared down the throat, the interior 

 of the mouth could be better and better observed. In this 

 large snake the membrane or skin was too thick to enable 



