270 



DISTRIBUTION OF VESSELS IN GLANDS. 



even some of the viscera, is distributed to the kidneys. But 

 whether the material for the secretion of the urine is afforded 

 from this source or not is doubtful ; for the kidneys here 

 still receive arteries of considerable magnitude, the finer twigs 

 of which form such tangled knots as we observe in the same 

 organs of birds and mammals. These tangled knots of ves- 

 sels, Malpighian bodies as they are called, constitute a form of 



vascular distribution that is pe- 

 culiar to the kidneys. They 

 are skein-like convolutions of the 

 arteries, which run in straight 

 lines between the tubuli uriniferi, 

 before resolving themselves into 

 the finest capillary net-works 



and 280 )' 



n Tied. n. Trevir. Zeitschrift, 

 B. 4, Tab. vi. 



Fig. 279. Malpighian bodies V^ ' T '' * 



of the kidney of the water-newt in largest numbers interspersed 



among the tubuli uriniferi of the 

 cortical substance (fig. 259, A and 

 E), but they are also observed 

 more thinly scattered in the medullary substance. The vessels 



of the most minute vascu- 

 lar net-works are every- 

 where much smaller from 

 twenty to thirty times small- 

 er than the finest coecal 

 and secreting glandular tu- 

 bules, and never terminate 

 in these, as they were once 

 universally, and as they 

 have even very recently, 

 been supposed to do. They 

 rather play round the in- 

 dividual terminal portions 

 of the glandular skeleton, 

 they never even penetrate 

 between the constituent cel- 

 lular elements of this. The 

 parietes of the blood-vessels 



Fig. 280. Malpighian bodies 

 from the kidney of an owl (Strix 

 aluco), fully injected and largely 

 magnified. 



appear to be of the very thinnest and most delicate description 

 in the glands.*] 



* This admirable article on the structure of glands is from Professor 

 Wagner's Physiology, pp. 384, et seg. ED. 



