THE ABDOMEN 



827 



Lymphaties. — These pass to the lateral group of lumbar glands, 



and to the internal iliac glands. 



Nerves. — ^These accompany the arteries, and are derived from 

 the renal, spermatic (ovarian in the female), and pelvic plexuses. 

 The fibres form plexuses in the fibrous and muscular coats, which 

 contain small ganglia. 



Middle Circular Muscular Fibres 



Outer Longitudinal Mnscnlar Fibres 



Inner Longitudinal Muscular 

 Fibres 



Transitional Epithelium 



Mucosa 



Fig. 357. — Transs^rse Section of the Lower Part of the Ureter, 

 SHOWING ITS Minute Structure. 



Structure of the Pelvis and Calices.— The structure of these 

 parts of the excretory apparatus resembles that of the ureter, with 

 the exception that they have only two layers of plain muscular 

 tissue, instead of three as in the ureter. The layer which is wanting 

 is the outer longitudinal layer. The calices are attached to the 

 bases of the papillae, and in these situations their fibrous coats 

 become continuous with that part of the fibrous capsule of the 

 kidney which is prolonged inwards through the hilmn to line 

 the sinus. The internal longitudinal muscular fibres disappear 

 towards the papilla, but the circular muscular fibres accompany 

 a calix to its termination, where they are arranged in the form of a 

 circular band, which surrounds the base of a papilla at the line of 

 attachment of a calix. The stratified transitional epithelium of 

 the mucous coat of a calix is prolonged over the apex of each 

 papilla. 



Stroma of the Kidneys. — Between the uriniferous tubules and 

 bloodvessels there is a certain amount of connective tissue, which 

 is present in greatest abundance in the region of the papillary zones. 



