310 



ZOOLOGY 



SECT.. 



of the auditory region : between the membranous wall of the 

 labyrinth and the investing bone is a small space containing 

 fluid, the perilymph. The labyrinth itself consists of the utriculus 

 with the three semi-circular cancels and the sacculus with the 

 lagena (cochlea). The utriculus (u.) is a cylindrical tube, bent 

 round at a sharp angle ; the semi-circular canals (ca. } ce., ep.) are 

 arranged as in the Frog (p. 265). A narrow tube, the ductus 

 endolymphaticus, leads upwards towards 

 the roof of the skull and ends blindly in- 

 the dura mater. The sacculus is large 

 and rounded. The lagena (I.) forms a 

 flattened not very prominent lobe, and 

 is of simple form. 



Urinary and Reproductive Sys- 

 tems. The kidneys (Figs. 920 and 921,. 

 /.) are a pair of irregularly shaped, dark 

 red bodies, each consisting of two lobes, 

 anterior and posterior, situated in close 

 contact with the dorsal wall of the pos- 

 terior portion of the abdominal cavity r 

 and covered with peritoneum on their 

 ventral faces only. Their posterior por- 

 tions, which are tapering, are in close 

 contact with one another. Each has a 

 delicate duct, the ureter, opening pos- 

 teriorly into the cloaca. A urinary bladder 

 (&/.), a thin- walled sac, opens into the 

 cloaca on its ventral side. 



In the male the testes (Fig. 920, t.) are 

 two oval white bodies, that on the right 

 f^ e situated just posterior to the right 



of the left testis and epididy- lobe of the liver, that on the left some- 

 mis is dissected away bl k * XL _J.L i~ i T'I 

 urinary bladder ; l.lg fold of Wliat lUrtner DaCK. Hiactl teStlS IS at- 



tiSSS?*PSS3t 2 tached . to the body-wall by a fold of 



cp posterior divisions of the the peritoneum, the mesorchium (ms 0} 



cloaca ; ep. epididymis ; i-. mi. -7-7 



kidney ; ms. o. mesorchium ; Ine cpiaiaymis (ep.) extends backwards- 

 KSSfffSSSSSSA from the irmer side of each testis, and 

 2^X l jSirtS?; ; P a f ses behind into a narrow er convoluted 



r. ridge separating anterior tube, the VaS dcfercnS Or SpermidllCt (v d } 

 and posterior divisions of u t. ^i 



cloaca ; ret. rectum ret ' its wnicii opens into the terminal part of 

 he the corresponding ureter. A pair of 



v ^?^r eversible copulatory sacs (p,p') t 

 which when everted are seen to be of 

 cylindrical form with a dilated and bifid 

 apex, open into the posterior part of the cloaca. 



In the female the ovaries (Fig. 921, ov.) are a pair of irregularly 

 oval bodies having their surfaces raised up into rounded elevations. 



FIG. 920. Male urinogenital 

 organs of Lacerta viridis. 



The ventral wall of the cloaca 

 is removed, the bladder 



