THE SPLEEN. 139 



In the latter we find, in addition, many peculiar white cor- 

 puscles, the splenic or Malpighian corpuscles, while abundant 

 vessels and a certain number of nerves are distributed through 

 its whole interior. 



§ 166. 



Coats and trabecular tissue. — The peritoneal investment 

 covers the whole surface of the spleen, with the exception of 

 the hilus, where, forming a sheath around the vessels and nerves, 

 it passes on to the fundus of the stomach as the ligamentum 

 g astro -lienale, and of the upper extremity, from which it 

 becomes detached, as the lig. phrenico-lineale ; it adheres so 

 closely to the fibrous coat in Man (though not in Ruminants), 

 that it can only be dissected from the organ in fragments. 



The fibrous coat (tunica albuginea seu propria) completely 

 surrounds the surface of the spleen, as a moderately thin and 

 semi-transparent but very strong membrane and at the hilus, 

 passes into its interior, like Glisson's capsule, accompanying the 

 vessels in the form of peculiar sheaths, the vaginas vasorum. 

 In Man, it is composed of common connective tissue, with 

 abundant networks of elastic fibres, whilst in some animals — 

 the Dog, Pig, Ass, Cat, (not in the Rabbit, Horse, Ox, Hedge- 

 hog, Guinea-pig, and Bat), I find it to contain smooth muscles in 

 considerable numbers. 1 



The trabecule of the spleen are white, shining, flattened or 

 cylindrical fibres, having, on an average, a diameter of j, — ±' ", 

 which are attached Fig< 2 26. 



in great numbers to 

 the inner surface of 

 the fibrous coat, and 

 less frequently to the 

 outer surface of the 

 sheaths of the vessels, 

 and unite with simi- 

 lar trabecules in the 

 interior, into a network which extends through the whole 

 organ. The interstices included in it all communicate, con- 

 Fig. 226. Transverse section through the middle of an Ox-spleen, washed out, to 

 show the trabeculee and their arrangement. Natural size. 



1 [The existence of these muscles in the ox's spleen was first pointed out by Dr. 

 Sharpey. See Quain and Sharpey's Anatomy, p. 1086.— Eds.] 



