THE FUNCTION OF THE SPLEEN. 105 



goes about an inch and a half; then, instead of being like other 

 veins, it becomes perforated on all sides. The beginning of this 

 canal has still a portion of the coats of the vein, but the form of 

 the whole canal is gradually effaced, so that nothing remains but 

 grooves in the cellular structure."* 1 



" This opinion was proved," says Blumenbach, " to be erroneous 

 by more careful examination of the human spleen e , which consists 

 entirely of blood-vessels, of enormous size in comparison with the 

 bulk of the organ : they are, in fact, proportionably more con- 

 siderable than in any other part of the body." 



But Dr. Andral affirms, that " by repeated washing, the spleen 

 is shown to consist of an infinite number of cells, which com- 

 municate on the one hand together, and on the other directly 

 with the splenic veins. The latter, when the inner surface of the 

 large subdivisions of the splenic veins are examined, appear to 

 have a great number of perforations, through which a probe 

 passes directly into the cells of the organ. The farther the sub- 

 divisions of the vein examined are from the trunk, the larger are 

 these perforations ; and still further on, the coats of the vein are 

 not a continued surface, but are split into filaments, which do not 

 differ from those forming the cells, and are continuous with them." 

 " The cells are produced in the following manner : from the 

 inner surface of the investing membrane of the spleen, a great 

 number of filaments, fibrous like itself, are detached, some of 

 which grow broad, and resemble flakes, and the latter chiefly 

 seem intended to support the divisions of the artery. In inter- 

 lacing each other, these filaments leave spaces, which are in fact 

 the cells of the spleen, and they terminate by insertion into the 

 walls of the veins, becoming continuous with the filaments into 

 which the veins are ultimately reduced." These facts are readily 

 ascertained in the spleen of the horse ; but may also be verified 

 in the human spleen. f 



" The experiments of Wintringham demonstrate the great 

 tenuity and strength of the coats of the splenic artery. It is 

 divided into an infinite number of twigs, the terminations of which 

 resemble pulpy penicillj and give rise to the splenic veins, which 

 gradually unite into large, loose, and easily dilatable, trunks." 



Andral says, that the splenic artery, almost as soon as it enters 



d Exposition Anatomique du Corps Humain, t. iv. p. 136. sqq. 



e " See Lobstein's Dissertation, Nonnulla de Liene sistens. Argent. 1773. 4to." 



f Precis d* Anatomic Pathologique, t. ii. P. i. p. 416. sqq. 



