STRUCTURE OF THE URETERS. 129 



bladder of the Frog. Their convolutions surround large yellow 

 ganglion cells, provided with a thick epithelial layer, first 

 desc/ibed by Jacubowitsch. 



URETERS. The ureters exhibit, as was stated at the outset, 

 a very similar structure to that of the urinary bladder. The 

 epithelium exactly resembles that of the bladder, and beneath 

 it is a layer of connective tissue, followed by a threefold muscular 

 tunic ; of which the innermost layer is longitudinal, the middle 

 circular, and the external, which is the thinnest, possesses a 

 less regular but essentially longitudinal course. A thin layer 

 of connective tissue forms a tunica adventitia, and is the most 

 external of the layers investing the ureters. 



The bloodvessels behave like those of the bladder. Engel- 

 mann * describes them as forming a subepithelial plexus in the 

 Kabbit, on which the epithelium is directly seated, without the 

 intervention of any connective tissue. In Man, however, 

 the layer of capillary vessels is less superficial and consequently 

 more protected. 



A small number of medullated nerves penetrate the ureter. 

 I have not been able to demonstrate the presence of ganglion 

 cells, except in the plexus of the adventitia, termed " funda- 

 mental " by Engelmann. 



BIBLIOGRAPHY. 



KOHLRAUSCH, Zur Anatomie und Physiologie der Beckenorgane, 1854. 

 BARKOW, Anatom. Untersuchungen iiber die Harnblase, 1858. 

 UFFELMANN, Zur Anatomie der Harnorgane. HENLE und PFEUFER, 



Bd. xvii. 

 BURCKHARDT, Das Epithelium der ableitenden Harnwege. VIRCHOW'S 



Arch., Bd. xvii,, p. 94. 

 LINCK, Ueber das Epithel der harnleitenden Wege. REICHERT and 



Du Bois' Archiv, 1864, p. 137. 

 SABATIER, Recherches anat. et physiol. sur les appareils musculaires. 



Montpellier medical, 1864. 

 SUSINI, Recherches sur rimpermeabilite de repithelium vesical. 



Journal de 1'Anatomie. Robin, 1868, p. 144. 



Pfliiger's Archiv fur Physiologie, 1869, Band ii., Heft 4 and 5. 



K 



