255 



What is a Sesamoid Bone ? 



One which is formed within a muscle tendon, and usually 

 near a joint, e.g., patella and fabellae of knee-joint, pisiform 

 of wrist, small bone nodules behind the metacarpo-phalangeal 

 joints, and epipubic bones of Marsupials. 



Write a Short Account of the Alimentary System of the Rabbit. 



There are four pairs of salivary glands, namely, parotid 

 (between external ear and mandible), infra-orbital (below 

 the eye), submaxillary (between the mandibles), and sub- 

 lingual (along inner side of lower jaw) ; the ducts open into 

 the mouth. The continuation of the buccal cavity beyond 

 the end of the soft palate is the pharynx ; it leads into the 

 gullet or oesophagus, which passes through the diaphragm 

 and opens into the stomach. The first portion of the small 

 intestine, the duodenum, forms a long U-shaped loop ; the 

 succeeding portion, the coiled ileum (about seven feet long), 

 ends in the sacculus rotundus which opens into the caecum 

 (first portion of large intestine) near its junction with the 

 colon. The large caecum (marked by a winding spiral 

 construction) ends blindly in the vermiform appendix, 

 and (proximally) is continuous with the sacculated colon, 

 which is followed by the long and narrow rectum, ending 

 at the anus. In herbivorous animals digestion is slower 

 and the amount of indigestible matter is greater than in 

 carnivorous types ; hence the greater length of bowel. 



The large five-lobed liver is attached to the diaphragm 

 by the suspensory ligament ; and partly embedded in it 

 (right central lobe) is the gall-bladder, from which the bile 

 duct passes (beside portal vein) to the duodenum (entering 

 it about a quarter of an inch from the pylorus). The diffuse 

 pancreas is spread out in the mesentery of the duodenal 

 loop ; the pancreatic duct opens into the distal limb of the 

 duodenum (inner side). 



The alimentary canal is supported by mesentery, i.e., a 

 double fold of the glistening peritoneum which lines the 

 abdominal cavity. The great omentum, a peritoneal fold 

 laden with fat, is connected with the stomach. 



A long-shaped crimson body attached behind the stomach 

 is the spleen. 



Describe the Brain of the Rabbit. 



See page 201 ; also " general features of Mammals," 

 page 250. 



