485 



each side, practically bilaterally symmetrical in location and dimension. 

 Distal isthmus (7, 7) smaller in caliber than the proximal (5, 3). 

 Nr. 141 (right), 142 (left) man aged 50. This is a typical pair of 

 ureters as to dilitations and constrictions and usual location. Calyces 

 (1, 1) not present. Pelvis (5, 2) moderately developed of the round 

 (right) end oval type (left). Proximal isthmus (5, 5) indistinct. Lumbar 

 spindle (i, 4). Middle isthmus (.3, 5) not well marked. Pelvic spindle 

 (Ö, 6) well marked bilaterally symmetrical in location and dimension. 

 In the right (141) a slight enlargement occurs at the distal end of the 

 pelvic ureter a second pelvic spindle. The distal isthmus (7, 7) is 

 considerably less in diameter than the proximal (5, 3). The right 

 ureter was V2 ii^^h longer than the left. Nr. 143 (right), 144 (left) 

 man aged 52. This pair of ureters shows numerous dilatations and 

 constrictions. Calyces (i, 1) mostly absent. Pelvis (5, 2) fairly well 

 developed of round elongated type (144) and oval type (143). Proximal 

 isthmus well marked but distally located, nonsymmetrical in dimension 

 and location. At the proximal isthmus (144) where the ureter was 

 small in diameter it rotated on itself while being distended with parafin 

 hence the parafin became interrupted at the proximal isthmus as noted 

 in the figure. Lumbar spindle (4, 4) typical with larger right (143). 

 Middle isthmus (5, 5) indistinctly marked. Pelvic spindle (6\ 6 a, 

 Ö, 6 a) bilaterally double, nonsymmetrical in dimensions and location. 

 Distal isthmus (7, 7) equal in diameter to proximal (5, 3). The left 

 ureter is one half inch longer than the right. Nr. 145 (right), 146 

 (left). A man aged 57. A typical pair of calyces (i, T) partially 

 present. Pelvis (5, 2) elongated, round type well developed. Proximal 

 isthmus (5, .5), right, located immediately adjacent to the pelvis {2\ 

 left, more distally located. Lumbar spindle (4, 4) right (145) large 

 and short, left long one and small one (i). Middle isthmus (.5, 5) 

 distinctly marked. Pelvic spindle ((>, 6 a) well marked bilaterally 

 doul)le symmetrical in dimensions and locations. The proximal" pelvic 

 spindle 6 a, 6 a, are the smaller, the distal (6', 6) are the larger. The 

 distal isthmus (7, 7) is much smaller than the proximal (.3, 3). 



When the ureter possesses double lumbar or pelvic spindle (as in 

 Nr. 145 and 146) the proximal spindle is generally the smaller while 

 the distal is the larger. This demonstrates the anatomic fact that 

 where a ureteral constriction (isthmus) exists from heritage or is 

 pathologic condition a ureteral dilatation will exist proximal to it. 

 For in securing some of the specimens in the illustration I am indebted 

 to Profs. W. A. Evans and O'Byme, Dr. Fred Harris and Dr. Tufts. 



