180 OPHIDIA. BOAD^. 



stomach, — at least, nothing is said of any other 

 part of the animal. I have never had an oppor- 

 tunity of dissecting the pulmonary system of a 

 Boa, or of satisfying myself as to the structure of 

 the extremely long trachea, which must be very 

 firm to resist such an immense pressure ; but I 

 believe, from a near and accurate inspection, in 

 company with others, that respiration goes on dur- 

 ing the period of the greatest dilatation. Wliile 

 these Serpents are in the act of constringing or 

 of swallowing their prey, they appear to be so"* 

 entirely pervaded with the appetite which then 

 governs them, that I am convinced they would 

 suffer themselves to be cut in pieces before they 

 would relinquish their victim. I have assisted in 

 taking them up and removing them with their 

 prey in their coils, without their appearing to be 

 in the least disturbed by the motion, excepting 

 that, if after the victim is no more, and the con- 

 striction is somewhat relaxed, an artificial motion 

 be given to the dead body, they instantly renew 

 the constriction. When thus employed they may 

 be approached closely, and with perfect security, 

 for the reason above stated ; and I have uniformly 

 found that the larynx is, during the operation of 

 swallowing, protruded sometimes as much as a 

 quarter of an inch beyond the edge of the di- 

 lated lower jaw.* I have seen, in company with 

 others, the valves of the glottis open and shut, 

 and the dead rabbit's fur immediately before the 

 aperture stirred apparently by the Serpent's 



* Since the publication of Mr. Broderip's Memoir, Mr. Joseph 

 Henry Green, in his lectures at the Royal College of Surgeons, ex- 

 hibited a drawing of two muscles which he had detected in the lower 

 jaw of the Boa, the purpose of which is to bring the larynx forward 

 during the operation of swallowing. 



