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J. B. Haycraft, 



nearer the medulla the advanced stages can be seen. The first budding 

 off of the tubules as are S shaped prolongations from the primarj' 

 renal vesicles has already been alluded to, and represented in Fig. 8. 

 A ftirther stage is represented in Fig. 9 and it will be observed 

 that the tubule has elongated and has passed deeper into the Kidney 

 substance, and away from the primary renal vesicle which has divided 

 into two; the stalk of each has elongated so that they preserve their 

 position at the periphery. The S shaped bend by the tubule is even 

 more marked than before and the free end is flattened out and moulded 

 upon the prominent bend of the tubule. This free terminal part is in 



Fig. 11. 



In this the glomerulus is he- 



ginniug to form, the epithelium 



covering it is still cuhical. 



B.C. 



Fig. 12. 



The glomerulus is fully formed 

 and the cuhical cells around 

 it have hecome squamous cells. 



shape like a shallow double walled spoon bowl and is the young 

 Bowman's capsule of the Malpighian body and in the connective tissue 

 at the spot G. the capillaries of the future glomerulus will form. At 

 this stage the epithelium of the tubule which is prolonged into the 

 Bowman's capsule thins away to flattened squames on the outer side, 

 while on the side covering the future glomerulus the cells are large 

 and cubical. In Fig. 10 the Malpighian body will be seen in a very 

 slightly more advanced condition, and the tissue in the position marked 

 G. is growing to form the glomerulus. In Fig. 11 this tissue has 

 grown, and is displacing the tubule, upon which the Bowman's capsule 

 had, as it were, been moulded; blood cavities and blood corpuscles may 

 be recognised within it, while the epithelium remains as before. In 

 Fig. 12 what is practically the adult condition is reached, the glome- 



