444 THE SOLIDS. 



" The peculiar features of this stage consist of an enlargement of the 

 arteries entering the corpora Malpighiana ; the dilatation of the vessels 

 of the tuft, the capillaries and the veins ; an increase in the size of the 

 capsule of the corpus and of the tubuli, and a large addition to the 

 quantity of the parenchyma of the organ. 



" The condition of the arteries is visibly changed, even at this early 

 period ; the artery entering the corpus being actually twice or thrice its 

 natural size ; which is the case also with the Malpighian tuft, and the 

 capillary vessels which spring from the tuft. An injection, in this stage, 

 cannot very easily be made to pass through the tuft and fill the capsule 

 of the corpus, a circumstance which almost always attends injection in 

 the later stages of the disease. 



" The capillaries and veins are greatly enlarged, giving to the surface 

 of the organ the resemblance of net-work. This is the commencement of 

 the stellated condition, which is so marked a characteristic of the next 

 stage of the complaint. 



" The tubuli in this stage are also much increased in their dimensions ; 

 but the fat which is found in them is soft and white. 



" The Second Stage of the Disease. The organ in this stage is very 

 greatly increased in size, its surface is smooth, and presents numerous 

 white spots ; the capsule is but slightly adherent to the surface, and the 

 tissue of the organ is flabby. 



" The structural changes exhibited during this stage are the fol- 

 lowing : 



" 1st. The artery of the corpus Malpighianum becomes so greatly 

 enlarged that frequently it equals the dimensions of the tube itself, and 

 is eight or ten times its natural size. It is tortuous and dilated, and 

 sometimes, previously to entering the capsule of the corpus, presents swell- 

 ings analogous to those of varicose veins. The primary branches of it, in 

 forming the tuft, are also distended to ten or fifteen times their natural 

 size, and are not unfrequently discovered external to the capsule of the 

 corpus, as though thrust out by some internal force. The vessels 

 forming the tuft are likewise enormously enlarged, and very often the 

 minutest branches are fully as large as the main artery of the corpus in a 

 healthy state. 



" Occasionally the tuft is broken up, and, instead of forming a compact 

 mass, exhibits its individual branches separated from each other. At 

 other times the branches of the tuft are actually larger than the primitive 

 artery of the corpus. Under these circumstances it is singular that Mr. 

 Bowman should have made the following remarks : ' Though I have 

 examined, with great care, many kidneys at this stage of the complaint, 

 I have never seen, in any instance, a clearly dilated condition of the 

 Malpighian tuft of vessels :' he adds, 'on the contrary, my friend Mr. Busk, 

 an excellent observer, has specimens which undoubtedly prove these 

 tufts not to be dilated in the present stage: and I possess injected 

 specimens showing them in all stages, but never above their natural size.' 



