150 TETRAO TETRIX. 



twelfths in diameter, but towards the end enlarged to eight- 

 twelfths. The cloaca, marked by an obscure valve or rim, on 

 which are seen the orifices of the ureters, and behind which is 

 the entrance of the bursa of Fabricius, is only half an inch long. 

 The coeca are nearly half the length of the intestine, being 

 thirty inches long. They come off vrith a large oblique aper- 

 ture, for six inches are nearly of the same diameter as the in- 

 testine, varying from three to four twelfths, then enlarge to 

 about twice its size, from eight to ten twelfths, and so continue 

 to the extremity, which is oblong, narrowed, with a nipple-like 

 termination. 



Under the tongue, in the angle of the lower mandible, is a 

 large mass of mucous cr}^3ts, of which there is also a series on 

 each side on the edoje of the tono^ue. The fauces and the whole 

 extent of the oesophagus are abundantly supplied w^th mucus 

 from cr}^3ts scattered over their whole surface, and which are 

 larger at the aperture of the crop. The latter organ, which is 

 extremely thin, has no mucous cryj^ts excepting around its 

 orifice. The proventriculus emits from its glandules a very 

 copious clammy fluid of a greyish colour, as well as a mucous 

 secretion from small crypts. These fluids pass into and line the 

 cavity of the gizzard. The inner surface of the small intestine 

 is even and villous in its whole length, excepting towards the 

 entrance of the coeca, where it is covered for about tw^o inches 

 with flattened tapering projections, which are larger below, and 

 disposed so as to form a kind of ring or imperfect valve between 

 the small intestine and the rectum. The latter is smooth and 

 even within, glandular, and plentifully supplied with mucus. 

 The coeca are internally villous, and, excepting for six inches 

 at the commencement, have their inner coat raised into seven 

 or eight longitudinal prominent ridges, which are thick, vil- 

 lous, and, being white, are seen externally through the muscular 

 and peritoneal coats. 



The liver is of two unequal lobes, the right two inches and 

 three quarters, the left two inches, long. There is no gall- 

 bladder ; and the biliary ducts enter at the distance of ten 

 inches from the pylorus. 



The bill is brownish-black, as are the claws ; the toes wood- 



