798 



SPLEEN. 



mine, for it is clear that the results of his ana- 

 lyses may solely depend upon this fact, that in 

 the animals he examined, the changes which 

 I have verified in the blood globules of the 

 spleen, were going on in an energetic manner. 

 If these visible changes of the blood globules, 

 which certainly occur in a most exquisite 

 manner in the horse and dog, if they be nor- 

 mal appearances, then is the diminution in the 

 quantity of the blood globules, which Be- 

 clard found on analysis, also a normal phe- 

 nomenon ; but if not, then he only examined 

 a blood partially deprived of its globules by 

 stagnation and effusion. The results of che- 

 mical analysis would then only be secure, if it 

 were at the same time shown, that there were 

 no visible changes of the blood globules in 

 the spleens of the animals examined. Until 

 this takes place, Beclard's conclusion will 

 remain, like mine, hypothetical ; although this 

 is in no way diminishing the merit of his ob- 

 servations, since I hold my own hypothesis 

 as one which I am perfectly justified in pro- 

 pounding in the present state of our know- 

 ledge. But even if we suppose that the blood 

 corpuscles are destroyed in the spleen, it is 

 nevertheless a question how this dissolution 

 is super-induced, and at what time it comes 

 to pass. As regards the first of these points, 

 in my writing previously mentioned I ex- 

 pressed the opinion, that the spleen is a con- 

 tractile organ, and may, by virtue of its con- 

 tractility, be able to dilate and contract itself, 

 - to fill itself with blood, and again to expel 

 the blood from it. In the state of filling itself 

 with blood, a stagnation of blood occurs in the 

 smaller vessels, perhaps even an extravasa- 

 tion ; and in this stagnant blood, the blood 

 globules undergo destruction, since they 

 slowly dissolve themselves, either free or in- 

 closed in cells. This view I still regard as cor- 

 rect. For, firstly, it is a matter of fact that the 

 spleen does enlarge and diminish its size, and 

 certainly under vital circumstances which are 

 altogether normal. Very many of the older 

 observers have accepted this fact ; as Lieu- 

 tand, Haller, Stuckeley, Rush, Clarke, Hodg- 

 kin, Home, and Dobson. This is shown by 

 an examination of the splenic region in the 

 living human subject (Piorry). So also it is 

 shown by vivisection . of animals, in whom 

 I have myself seen (and especially in the dog) 

 a very distict diminution and rounding of its 

 outer surface. Finally, Landis *. by weighing 

 the spleen, has recognised a distinct increase 

 and diminution of weight. He examined at 

 different times thirty rabbits, and finds that 

 the average weight of the organ in five obser- 

 vations was : 



12 hours after eating, 0'768 grammes.f 



5 



8 

 24 



48 



2 



588 

 548 

 526 

 510 

 444 



Now although it may be freely conceded that 



* Loc. cit. 



t The " gramme " is 15 grains Troy English. 

 (Transl.) 



an organ like the spleen is subject to so many 

 variations in respect of size as to render 

 thirty observations much too small a number 

 to afford any very definite information con- 

 cerning its increase or decrease of size, it 

 must, nevertheless, be considered, that Landis 

 has examined the proportion of the spleen to 

 the whole body, and to many other organs, 

 as the stomach, liver, and kidneys, and that 

 from this means he derived a confirmation of 

 what the estimate of its absolute weight had 

 previously taught ; so that his observations 

 must be regarded as a meritorious contri- 

 bution to our knowledge respecting the 

 changes of volume which the spleen expe- 

 riences. We now ask, secondly, how these 

 changes come to pass ? Beclard states that the 

 spleen enlarges and becomes filled with blood 

 in consequence of the splenic vein being com- 

 pressed by a muscular force ; but the nature 

 of this he has not stated, nor can I regard his 

 view as correct. I believe myself to have 

 propounded a better theory when I stated, 

 that the spleen becomes turgescent in conse- 

 quence of the relaxation of the muscular 

 fibres which exist in its balks, coats, and 

 vessel-sheaths ; or in animals from whom 

 these are absent, through a relaxation of the 

 muscular fibres of the vessels themselves. 

 A constriction of the splenic vein cannot be 

 supposed to obtain, since the muscular fibres 

 which it contains are but very little de- 

 veloped, and no other compressing force is 

 present ; while, on the contrary, we know that 

 in all animals the splenic artery is uncom- 

 monly muscular, and that the partitions of the 

 spleen themselves contain distinct muscular 

 fibres. It is these muscles and no others 

 which, according to my researches, produce 

 the distension of the spleen ; but not through 

 their contracting together, but by their re- 

 laxation, which brings with it a distension of 

 the vessels with blood, and a slower circu- 

 lation of this fluid. The diminution in the 

 size of the spleen occurs simply through the 

 contraction of the muscular parts just named. 

 Precisely in the same manner the corpora 

 cavernosa of the penis become filled with 

 blood by a relaxation of the muscles situated 

 in their fibrous partitions ; and become poorer 

 in blood, and smaller in size, when the mus- 

 cles again contract themselves. Of course, 

 both here and in the spleen, the nerves play 

 an important part in the process ; probably in 

 consequence of antagonistic relations be- 

 tween them and other parts of the nervous 

 system, which at present cannot be accu- 

 rately indicated. Thirdly, and finally, it may 

 be asked, whether the blood corpuscles simply 

 dissolve because the blood of the spleen be- 

 comes stagnant at certain times, or whether 

 special influences are necessary to this effect ? 

 whether the parenchyma of the spleen or 

 the Malpighian corpuscles may not secrete a 

 juice, a " succus lienalis" of which the earlier 

 authors speak, which exerts a solvent in- 

 fluence on the blood corpuscles ? As a kind 

 of vague answer to this question, I have ex- 

 amined the parenchyma with respect to its 



