514 THE RABBIT CHAP. 



what displaced backwards to show the ramifications of the coeliac artery (cce. a) ; 

 the duodenum is spread out to the right of the subject to show the pancreas (pn) 

 the branches of the bile-duct (c. b. d), portal vein (p. v) and hepatic" artery (h, a) 

 are supposed to be traced some distance into the various lobes of the liver. 

 a. m. a. anterior mesenteric artery ; cau. caudate lobe of liver with its artery, vein 

 and bile-duct ; c. b. d. common bile-duct ; cd. st. cardiac portion of stomach ; 

 c. il. a. common iliac artery ; cce. a. coeliac artery ; cy. a. cystic artery ; cy. d, 

 cystic duct ; d. ao. dorsal aorta ; du. proximal, and du'. distal limbs of duo- 

 denum ; du. a. duodenal artery ; du. h. a. (in A], duodeno-hepatic artery ; g. a. 

 gastric artery and vein ; g. b. gall-bladder ; h. a. hepatic artery ; h. d. left hepatic 

 duct ; I. c. left central lobe of liver, with its artery, vein, and bile-duct ; 1. g. v. 

 lieno-gastric vein ; I. I. left lateral lobe of liver, with its artery, vein, and bile- 

 duct ; ms. branch of mesenteric artery and vein to duodenum ; ms. r. mesentery 

 of the rectum ; m. v. chief mesenteric vein ; ces. gullet ; p. m. a. posterior 

 mesenteric artery ; p. m. v. posterior mesenteric vein ; pn. pancreas ; pn. d. 

 pancreatic duct ; p. v. portal vein ; py. st. pyloric portion of stomach ; ret. 

 rectum ; r. c. right central lobe of liver, with artery, vein, and bile-duct ; spg. 

 Spigelian lobe of liver with its artery, vein, and bile-duct ; spl. spleen ; sp. a. 

 splenic artery. (From Parker's Zootomy.) 



right, is less dilated and has much thicker muscular 

 walls. The mucous membrane of the stomach, in 

 which the microscopic gastric glands (p. 131) are con- 

 tained, is raised into ridges or ruga, and there is a 

 circular pyloric valve at the entrance to the intestine. 



The duodenum (du) extends backwards along almost 

 the whole length of the abdomen and then turns for- 

 wards again, forming a slightly coiled U-shaped loop, 

 and becoming continuous with the very long and coiled 

 second portion of the small intestine or ileum (Fig. 

 135, H), which finally dilates to form a rounded sac (s. r) 

 opening into the proximal end of the dark-coloured 

 colon (col), or first portion of the large intestine. The 

 colon has a much greater diameter than the small 

 intestine, and presents a series of sacculations arranged 

 in three rows, separated by flat regions of its wall : it 

 passes insensibly into the second portion of the large 

 intestine or rectum (ret), which is of about the same 

 diameter as the small intestine, and is recognisable by 

 its rounded swellings containing the pill-like faeces : it 

 passes into the pelvic cavity to open by the anus (a). 

 At the junction of the ileum and colon is a relatively 

 enormous blind-gut or cacum (ccec) a structure not met 

 with in either the dogfish or the frog, and only reaching 



