20 



bony palate as far as the circular aperture of the posterior nares. 

 The sides of the soft palate are continuous with the tongue, and, 

 becoming gradually contracted, form fauces of a funnel shape, the 

 posterior aperture of which just admits a black-lead pencil of the 

 usual size for drawing. The membrane covering the posterior part 

 of the dorsum of the tongue is continued smoothly and uninter- 

 ruptedly to the epiglottis, without the production of any fold of 

 membrane in front of this part, nor was there any corresponding 

 duplicature above, or at the sides of, the fauces : so that here no 

 structure existed that would allow any part of the fauces to be pro- 

 truded in a conical form into the pharynx, beyond the opening of 

 the glottis, as in the Capybara and Guinea-pig . 



The fauces of the Rat are formed after the same type as those of 

 the Beaver : a type which is peculiar, inasmuch as there is properly 

 speaking no velum pendulum palati, the membrane forming the root 

 of the fauces being continued straight, without duplicature or re- 

 flection, to the posterior aperture of the nares : this aperture is of a 

 circular form, on a horizontal plane, and situated immediately above 

 the glottis. 



The muscular apparatus of t\\Q fauces consists of a pair of muscles 

 which arise, one from each side of the tongue, and ascend, the 

 fibres diverging a little ; their action is to contract the commence- 

 ment of the fauces, being analogous to the palato-glossi : besides 

 these there are, at the narrower part of the fauces, circular fibres, 

 apparently continued from the superior constrictor of the pharynx, 

 and analogous to the palato-phary?igei. 



There are no palatal arches, neither were any tonsils detected. 



The peculiar cardiac gland much resembles tonsils in structure, 

 being composed of numerous small glands or follicles, forming an 

 aggregate of about 14 lines in length and half an inch in thickness, 

 which pour a viscid secretion, by numerous apertures, into the inte- 

 rior of the stomach. 



The pancreas is of considerable extent, measuring in length nearly 

 two feet, and following the course of the duodenum down to the 

 iliac region and up again as far as the umbilical, being attached to 

 the intestine by a process of mesentery : it is thin and narrow, and 

 has one small branch or process lying parallel with its body where 

 it passes behind the liver, and a few others at the curvature of the 

 duodenum. Its duct, somewhat larger than a crow-quill, enters the 

 small intestine at the extremity of the gland, one foot and nine 

 inches from the pylorus, and one foot and six inches from the ter- 

 mination of the ductus choledochus. 



At the commencement of the colon there are two pouches of an 

 oval form, from the union of which the rest of the intestine proceeds 

 with very distinct sacculi. An analogous structure exists in the 

 caecum of the Guinea-pig, where however the two sacculi appear 

 rather to belong to the ccecum, being partially separated from the 

 colon by a circular production of the lining membrane in a valvular 

 form. 



