350 THE SPLEEN, BY WILHELM MULLER. 



arranged bands of smooth muscular tissue. In injected pre- 

 parations a rich plexus of veins comes into view at this part, to 

 the walls of which most, if not all, of the smooth muscles must 

 be attributed. 



The interior of the organ is traversed by septa given off at 

 tolerably regular intervals from the internal surface of the 

 capsule. The structure of these processes agrees with that of 

 the capsule, and they intercommunicate with one another in 

 the interior of the organ. They form stellate expansions ; their 

 connective tissue becoming infiltrated with lymph corpuscles, 

 which in this modified form occupies all the interspaces of the 

 proper parenchyma of the organ. This last appears in the form 

 of spheroidal masses (globi or follicles), the diameter of which, 

 in the ordinary domestic animals, varies from 0'5 to 0'75 milli- 

 meter. The follicles themselves are composed of cells and a 

 retiform intermediate substance. 



The cells agree with the lymph corpuscles of the animals in 

 question, consisting of a mass of protoplasm containing a 

 nucleus, but destitute of a cell wall. Larger morphological 

 elements are constantly found intermingled with them, con- 

 taining two or three nuclei which may be regarded as the 

 result of a process of multiplication. At the periphery of 

 each follicle the cells lie more closely packed together than 

 near the centre, and in the fresh state they are connected 

 together by a pale finely granular tenacious intermediate sub- 

 stance. In preparations that have been hardened by diluted 

 Yi solutions of chromic acid, a plexus of delicate fibres may be 

 * recognised. This plexus is more distinctly fibrillar, and its 

 meshes are more elongated near the periphery of the follicle 

 than elsewhere, and the interspaces are here also filled with 

 closely compressed lymph corpuscle-like cells. This more com- 

 pact plexus extends beyond the limits of the follicles, so that 

 neither in the fresh nor in the hardened state can a continuous 

 investing membrane be demonstrated around them. 



The bloodvessels of the spleen of Reptiles consist of arteries, 

 capillaries, and veins. The artery enters the spleen of Ophi- 

 dians at the part opposite the pancreas, which is sometimes 

 hollowed out in the form of a hilus, and runs towards the 

 centre, enclosed in a membrane-like investment of connective 



