196 SPECIAL HISTOLOGY. 



so'" from the surface, as well as in the septa Bertini, down to 

 the sinus of the kidney and are disposed so regularly and in 

 such numbers, around the cortical lobules, that every transverse 

 section through the cortex always displays a red streak, caused 

 by these corpuscles, between each two lobules. Usually each 

 of these streaks consists of a minute artery, with from two to 

 four, of Malpighian bodies supported by it, but not in regular 

 series, some of which stand more in relation with the one, and 

 others with the other cortical bundle. Each fasciculus of 

 tubuli uriniferi, therefore, upon entering the cortical substance, 

 is, from the first, entirely encompassed by the Malpighian 

 bodies, and it is obvious that some of the tubuli quit it soon 

 and others later, in order to reach their appropriate Malpighian 

 bodies. For the rest, each cortical tubule, after its origin, is 

 much convoluted, runs at first somewhat outwardly, and then 

 returns upon itself, to join the straight tubules of the cortical 

 fasciculus. 



[The number of the convoluted tubuli uriniferi corresponds 

 with that of the Malpighian bodies and is, consequently, in every 

 instance, very considerable. According to Huschke, 200 tubuli 

 exist in each fasciculus corticalis, and 700 such fasciculi in a 

 pyramid; which calculation gives, in fifteen pyramids,, more 

 than two millions of commencements of tubuli and Malpighian 

 bodies. Since each papilla has about 500 or even more 

 orifices, it is possible that each cortical fasciculus proceeds 

 from a single "duct of Bellini f in any case, it is evident that 

 in every straight tubule the divisions are repeated at least ten 

 times. 1 ] 



§ 188. 



The tubuli uriniferi, are everywhere composed essentially of 

 the same elements ; viz. of a membrana propria, and a tesse- 

 lated epithelium. The former is a perfectly structureless, trans- 



1 [It would scarcely be deduced, from what is said in the text, that the tubuli 

 uriniferi, in the cortical part of the kidney, anastomose very freely and frequently, 

 although the fact of their doing so has been long well known and often described. 

 These anastomoses, however, and the general disposition of the tubules, are more 

 particularly adverted to and well depicted by Toynbee (' Med. Chir. Transact.,' 2d 

 ser., vol. XI, p. 308, pi. 7).— Eds.] 



