336 SECRETION. 



bear a close resemblance to the closed follicles of tlie small 

 intestine. 1 The investing membrane has no epithelial lining, 

 and the contents consist of an albuminoid liquid, with numer- 

 ous small, nucleated cells, and a few free nuclei. The cells 

 measure from -g-^ViF to -g-gVir of an inch in diameter. Both 

 the cells and the free nuclei of the splenic corpuscles bear a 

 close resemblance to cells and nuclei found in the spleen- 

 pulp. The corpuscles are surrounded by blood-vessels, 

 which send branches into the interior to form a delicate 

 capillary plexus. 3 



The number of the Malpighian corpuscles in a spleen 

 of ordinary size has been estimated by Sappey at from seven 

 thousand to eight thousand. 3 They are readily made out in 

 the ox and sheep, but are frequently not to be discovered in 

 the human subject. In about forty examinations, in man, 

 Sappey found them in only four ; but in these they presented 

 the same characters as in the ox and the sheep, and resisted 

 decomposition for twelve days, 4 showing that it is not neces- 

 sary to have recourse to perfectly fresh specimens to dis- 

 cover them if they exist. Kolliker notes the fact that they 

 are often absent in the human subject when death has taken 

 place from disease or long abstinence. He believes that 

 they are nearly always to be found in perfectly healthy per- 

 sons. 6 The occasional absence of these bodies constitutes 

 another point of resemblance to the solitary glands of the 

 small intestine. 8 



The relations of the Malpighian bodies to the arterial 

 branches distributed through 'the spleen are peculiar. In 

 specimens in which these corpuscles are easily made out, if 

 a thin section be made, and the spleen-pulp be washed away 

 by a stream of water, the corpuscles may be seen attached 

 in some parts to the sides of the vessels, in others lying in 



1 See vol. ii., Digestion, p. 321. 



2 KOLLIKER, Handbuch der Gewebelehre, Leipzig, 1867, S. 456. 



3 SAPPEY, op. cit., p. 326. 4 Idem., p. 325. 



6 KOLLIKER, op. cit., S. 454. 6 See vol. ii., Digestion, p. 319. 



