482 



7) Van P£e, P., Recherches sur le d6veloppement des extr^mit^s chez 

 Amphiuma et Necturus. Extr. des C. rendus de I'Assoc. des Ana- 

 tomistes, V. Session, Liege 1903. Avec 5 fig. 



8) — — Ueber die Entwickelung der Extremitäten bei Amphiuma und 

 Necturus. Verhandlungen der Anatom, Gesellsch., 17. Vorsammlung 

 Heidelberg 1903. 



Nachdruck verboten. 



Constrictions and Dilatations of the Ureter. 



By Byron Robinson, B. S. M. D., Chicago. 

 With one Figure. 



The specimens of the ureters in the accompanylng illustrations 

 were prepared by removing the ureter from the body, dissecting it 

 free and injecting under similar pressure liquid parafin. The ureters 

 are mostly pairs and hence serve for comparison. They were painted 

 white so that a clear outline would be presented after which Dr. 

 Wm. E. Holland photographed them. Ureteral constrictions, dilatations 

 and spirality were plainly evident. The clinical signification of the 

 ureteral isthmuses are flexion and the obstruction consequent of the 

 urinal stream, also obstruction of calcuH as demonstrated by the x-ray. 

 The ureteral dilatations, the results of the constrictions, entertain 

 calculi. Ureteral surgery should be executed at the ureteral dilatations 

 where ample wall and lumen exist for manipulation. Limited surgery 

 can be executed at the ureteral isthmuses on account of lack of wall 

 and lumen for manipulation. 



The figure (half life size) illustrates the form and dimensions of 

 the ureters of man, pig, cow, sheep, by means of liquid parafin injected 

 into the ureteral lumen under similar pressure. The ureteral calyces 

 (i, 1) are frequently presented. The ureteral dilitations 1) ureteral pelvis, 

 2) lumbar spindle (4), pelvic spindle (tf, 6) and ureteral constrictions or 

 isthmuses : proximal isthmus (5), middle isthmus (5), distal isthmus (7), 

 are distinctly pronounced and constant. Nr. 126 and 127 cow, length 

 26 and 24,6 inches. Calyces (i, 1). Pelvis (^, 2). Proximal ureteral isth- 

 mus (5, 3). Lumbar spindle (i, 4). Middle ureteral isthmus (5, 5). Distal 

 ureteral isthmus (7, 7). At the distal end of the ureter of cow and 

 that of the horse the ureter presents a bulbous enlargement. This 

 cow's ureter show excellent dilitations (spindles 4, 4) and constrictions 

 (isthmuses, 5, 3 and 7, 7). These specimens with others from the 



