THE SPLEEN". 



585 



one-half the mass of the spleen. There are no special investments 

 around these parenchymal cells. They lie in direct contact with 

 the sheaths of the vessels, the trabeculas, and the sheaths of the 

 Malpighian bodies. 



The red pulp of the spleen presents different shades at different 

 times, as they depend on the blood-corpuscles in its vessels; and 

 which present all the various stages of metamorphosis. Kolliker 

 and Gray ''describe round cells ^Vo- to H ^ of an inch in diameter, 

 holding more or less metamorphosed blood-corpuscles, and con- 

 taining 1 to 10 or even 20 of them. These, with other masses of 

 corpuscles without an investment, finally become converted into 

 pigment-masses and pigment-cells, after undergoing various changes 

 in color. Finally, however, the last pass into perfectly colorless 

 cells. The more recent investigations, however, of Eemak and T. 

 Wharton Jones, throw doubt 



upon the existence of these Fi S- 412 



red -corpuscle- inclosing cells; 

 especially in the normal state. 

 Eeddish crystalline forms 

 (hsematine) are also occasion- 

 ally found in the pulp. ( Gray.) 



3. The Malpighian bodies 

 are white, rounded masses im- 

 bedded in the red substance 

 of the spleen, and connected 

 with the smallest arteries. 

 Kolliker states that they 

 are constant only in healthy 

 subjects, and are found rare- 

 ly, or not at all, in those dy- 

 ing of disease, or after long 

 fasting. Gray, however, as- 

 serts that they are always 

 present in the mammalia, 

 though not always visible to 



the naked eye. They are T J^ to ^ (average J%) of an inch in dia- 

 meter ; being larger after food has been taken. Though imbedded 

 in the red pulp, and hardly separable from 4 it, they are always at- 



A portion of the splenic artery, its ramifications be- 

 ing studded with Malpighian corpuscles (dog). (Mag- 

 nified 10 diameters.) 



1 On the Structure and Use of the Spleen. London, 1854. 



