345 



I have not found these bodies by any means as common as in- 

 dicated by Kolliker, and, when present, they appeared as often 

 uninclosed as inclosed by a capsular membrane. It is true, 

 that in the rabbit and some other rodents, where they were most 

 constantly present, they appeared regularly saccular ; but in 

 reptiles and birds, they were oftenest of all shapes and sizes. I 

 have thus examined more than fifty fishes, thirty reptiles, and 

 great numbers of birds and mammals. These bodies seemed to 

 have no constant, functional relation to the tissue in which they 

 were found, and my conclusion is, that the blood-corpuscle-hold- 

 ing cells of Kolliker are only accidental formations, in fact, are 

 minute extravasations of the blood into the splenic tissue, and 

 which may or may not be invested with a capsular membrane 

 according to the plasticity of the material with which they are 

 surrounded. 



This view is substantiated by many facts and observed pheno- 

 mena. In some cases, if blood drawn from the living body be 

 allowed to stand, there will be found at the bottom of the vessel 

 roundish aggregations of blood-globules invested with a plastic 

 membrane. 



This has been noticed both in health and disease, and these 

 phenomena were conspicuously observed in the blood of an ele- 

 phant, which was procured for me by its keeper. The same has 

 also been observed in disease, where blood was extravasated into 

 the brain, and where these capsules thus formed, inclosed hetero- 

 geneous elements. (See Edinb. Month. Jour. Med. Sc. Sept. 1851.) 



I would, therefore, in conclusion, state that I regard these 

 peculiar bodies, on which Kdlliker has laid so much functional 

 stress, as only unusual and accidental forms, and which, there- 

 fore, sustain no important relations in the uses of the spleen. 



In this connection, it may not be amiss for me to make a re- 

 mark on the most probable nature and function of the spleen. I 

 have carefully examined this organ in all the classes of vertebrates 

 pretty extensively, and in man in disease as well as in health ; I 

 have also studied it in very many different conditions of the same 

 animal, while developing, while the animal was well fed, and 

 when partially starved. 



In these cases it seemed to sustain important and constant rela- 



