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(continuations of femorals), and two internal iliacs (=sci- 

 atics). 



4. The portal vein, which enters the liver (hepatic portal 

 system), is formed by the union of the lieno-gastric, duodenal, 

 anterior and posterior mesenteric veins. 



Where is the Thymus Gland situated ? 

 In front of the heart. 



Give a Short Account of the Respiratory Organs of the 

 Rabbit. 



The lungs, separated by the mediastinum, occupy the 

 lateral portions of the thorax ; they are attached at their 

 roots only, and each is enclosed in a pleural sac. The 

 trachea (seepage 212) divides into the right and left bronchi, 

 which enter the lungs (at their roots) and form a ramifying 

 system of bronchial tubes. The diaphragm is dome-shaped 

 and its margin is muscular ; when it contracts, the dome 

 is flattened, the thoracic cavity is consequently enlarged, 

 and the lungs then expand (inspiration). 



Describe the Urino-genital Organs of (I) the Male, and (2) the 

 Female Rabbit. 



(1) The two ovoid kidneys (metanephros) are embedded 

 in fat on the dorsal wall of the abdomen, above the peri- 

 toneum. The ducts or ureters issue from the inner sides 

 (at the kidney notch), and pass back to open into the 

 bladder, the outlet of which forms the urino-genital sinus 

 (urethra of male, vestibule of female). At the front of each 

 kidney there is a yellow suprarenal gland. 



The two testes, originally near the kidneys, descend later 

 into the scrotal sacs, pouches of the abdominal wall. The 

 neck of each sac is the inguinal canal. Each testis has an 

 associated epididymis (mesonephros or Wolffian body). 

 Through the tubes (vasa efferentia) of the epididymes, 

 the spermatozoa pass into the vasa deferentia (Wolffian 

 ducts), which enter the abdominal cavity, and, looping 

 round the ureters, pass back to open separately through a 

 sac (uterus masculinus) into the urethra. Upon the uterus 

 masculinus and vasa deferentia are the prostate glands, 

 and behind these are Cowper's glands. The urethra tra- 

 verses the penis, which projects from the ventral surface 

 of the body, in front of the anus. 



