54 



T. H. BURLEND, 



Aorta-" 



Text%. C (1—9). 



Textfig. C (1—50). A series of diagrams of successive sections of the anterior 

 end of the left kidney of Embryo P, showing the gradual transition from pronephros 

 to mesonephros. The vascular tissue has been shaded, and the blood- corpuscles 

 shown as black patches. Diagram 1 is taken from section 3,11, so that diagram 

 14 will represent section 3,24. Note the change in the position of the uephrostomes 

 as one passes from the anterior to the posterior end. of the pronephros. 



