348 THE URINU-GENITAL SYSTEM, THE ADRENALS, ETC. 



(2) The M. compressor cloacae arises from the tip o£ the urostyle, 

 and is inserted into the hinder end of the rectum; it is also 

 attached to the symphysis of the iliac bones ; from this point a few 

 fibres j)ass to the anus (Hoifmann).] 



III. THE ADRENALS. 



a. General description. 



Fig. 226. 

 Cv Ao 



The male uiino-genital organs. 

 Ao Aorta. 

 CI Cloaca. 

 Cv Inferior vena cava. 

 FK Pat-body. 

 N Kidney. 

 S, Si Openings of ureters. 

 T Testis. 

 Ur Ureter. 

 Vr Renal veins. 



t Appearance of ureters on the ven 

 tral surfaces of kidneys. 



The adrenals are small yellow bodies 

 attached to the renal veins on 

 the ventral surface of the kid- 

 ney, towards its outer border. 



b. [Minute structure. The 



superficial layer of the adrenals 

 consists of solid, rounded, or 

 elongated grovips of polygonal 

 cells, containing numerous fat- 

 granules; these represent the 

 cortical substance of the corre- 

 sponding organs of higher ani- 

 mals. The medullary part is 

 present only in small quantity; 

 it consists of small groups of 

 polygonal cells, placed between 

 trabeculae of connective-tissue ; 

 both trabeculae and cell-groups 

 are covered with an endotheliimi . 

 The whole organ is surroundea 

 by a connective-tissue capsule, 

 which sends in trabeculae to 

 support the parenchyma (Hoff- 

 mann). 



No nerves have been traced into 

 these organs (Eberth).] 



IV. THE FAT-BODIES. 



a. General description. The fat-bodies (Fig. 226) are bright 

 yellow, lobulated bodies, placed in front of the testes and ovaries 

 respectively. The greater portion of each organ lies parallel to the 

 long axis of the body, and from its anterior, posterior, and external 



