776 



SPLEEN. 



The Malpighian corpuscles are imbedded in 

 the red spleen substance, and, with the ex- 

 ception of one point, where they are attached 

 to arterial twigs, they are everywhere sur- 

 rounded by this substance. They are con- 



Fis. 526. 



A small arterial trunk with Malpighian corpuscles, on 

 a somewhat larger artery. From the spleen of the 

 Pig. Magnified 10 diameters. 



a, the artery ; b, the sheath of the same ; c, Mal- 

 pighian corpuscles ; d, pencils or tufts of arteries. 



nected to the small arteries and their twigs by 

 short peduncles, like the berries of a bunch 

 of grapes ; and, in such wise, that a small 

 arterial trunk of from 2 to 4-100ths line, with 

 its ramifications, supports 5 to 10 corpuscles. 

 (Fig. 526.) The peduncles of the corpuscles 

 are almost always small arteries, which pass 

 to be distributed to them ; but in less frequent 

 instances, they are constituted by short pro- 

 cesses of the arterial sheaths, which are con- 

 tinuous with the membranous wall of the 

 corpuscle. In this manner the majority of the 



Fig. 527. 



A Malpighian corpuscle from the spleen of the Ox in 

 connection with a small artery, magnified 150 dia- 

 meters. 



a, wall of the Malpighian corpuscle ; b, contents of 

 the same ; c, coat of the artery ; d, sheath of the 

 same. 



corpuscles are essentially devoid of a peduncle, 

 and sit immediately on the arteries at their 



points of bifurcation, or at their sides, (Figs. 

 527, 258.) This relation, which also obtains 



Fig. 528. 



Malpighian corpuscle from the spleen of the Pig in 

 connection with an artery from which a branch 

 passes to the corpuscle. Treated with soda, and 

 magnified 250 diameters. 



a, wall of the corpuscle ; b, elastic fibres in the same ; 

 c, sheath of the artery ; d, dissolved middle tunic 

 of the artery; e, elastic inner coat. 



in animals, formerly appeared to J. Miiller as 

 indicating the fact that the splenic corpuscles 

 were hollow excrescences of the vessel-walls, 

 or were imbedded in these latter. But if by 

 this be understood, what Miiller's plates and 

 description imply, that the sheaths of the 

 vessels, in their whole thickness, with all their 

 elements, are continued to form the cor- 

 puscles, then it is certainly incorrect : for in 

 some animals I have seen that, from the rich 

 network of elastic fibres and muscular struc- 

 ture of these sheaths, little or nothing passes 

 to the corpuscles : and I have generally found 

 the membrane of the corpuscle very delicate. 

 It is, however, quite conformable to truth, to 

 state that this membrane has a direct con- 

 tinuity with the arterial sheaths. (Fig. 527, 

 528.) 



The corpuscles do not possess any con- 

 nection with the trabecular network, still less 

 that which Gerlach has lately attributed to 

 them : viz. that they serve as points of sup- 

 port to the elastic fibres of the partitions ; a 

 belief which is altogether baseless. 



It is difficult to say any thing definite re- 

 specting the number of the splenic corpuscles. 

 Hessling believes that, in some cases, they 

 constitute from one-fifth to one-sixth of the 

 whole splenic mass ; and this seems to me no 

 overstatement, if we substitute the expression 

 " spleen-pulp " for " spleen-mass." At least, 

 I have found, that their quantity is very 

 considerable; and that in some instances, 

 when they are rather turgescent, the whole 

 pulp appears as if besprinkled with white. 

 They stand so thickly together, that in many 

 places they touch each other's sides ; and in 

 others are only separated from each other by 

 narrow interspaces, which in the least favour- 

 able circumstances are about one to two lines 

 in size. I believe that the estimate, that one 

 and a half to two lines of spleen-pulp con- 



