714 ^* ^* GREGORY, Development of the excretory system in Turtle?. 



Fig. 63. Mesonephric blastema (mes. bî) and Wolffian duct (w. d). 

 Figs. 64 — 68. Consecutive sections. Figs. 65 — 67 accidentally 

 of slightly lower magnification than the others. 



Plate 49. 



Figs. 69 — 71. From cross sections of Tlatypeltis XVI (2). 



Fig. 69. Ureter {ur) and metanephric blastema (met. hi). Meso- 

 nephros consisting of several coiled tubules with three glome- 

 ruli on the right and two on the left and with three openings 

 into the duct on the left. Blastemic tissue is still seen on 

 the median dorsal side of the kidney lobe. 



Fig. 70. Shows apparent branching of the ureter. 



Fig. 71. Forty-one sections before the branching of the ureter 

 from the duct. 



Plate 50. 



Fig. 72 — 75. Combined from two sagittal sections of Platypeltis 

 embryo XVI (1). The drawing may be made complete by joining the 

 lower end of one figure to the upper end of the following. 



Fig. 72. Anterior end of mesonephric region and remnant of 

 glomus of pronephros with pronephric tubules at the anterior 

 end. 

 Fig. 73. More anterior part of the mesonephros with glomeruli 



very distinct. 

 Fig. 74 — 75. The posterior end of the mesonephros with part 

 of the Wolffian duct and the blastema of the metanephros 

 with a part of the ureter. 



Frtmmannsch« Buchdrnckerei (Hermann Poh!e) in Jena — 2070 



