3& APPENDIX, 



assiduous in that investigation, without, however, determining the much disputed point, 

 whether or no this viscus possesses a proper or glandular structure, or is it simply a 

 minute and infinite interlacement of arteries, veins, and lymphatics. Sir Everard 

 Home concludes from his researches, that, " it consists of blood-vessels, between which 

 there^isno cellular membrane, and the interstices are filled with serum, and the colour- 

 ing matter of the blood from the lateral orifices in the veins, when these vessels are in 

 a distended state ; which serum is afterwards removed by the numberless absorbents 

 belonging- to the organ, and carried into the theoracic duct by a very large absorbent." 

 Sir Everar;' considers " the spleen, from this mechanism, to be a reservoir for the super- 

 abundant serum, lymph globules, soluble mucus and colouring matter, carried into the 

 circulation immediately after the process of digestion is completed. 



M. Beclard, (additions to the anat. genewle of Bichat,) has given an opinion respect- 

 ing the structure of this viscus, which appears to be the most correct yet offered. He 

 considers that it belongs to the class of erectile tissues, and that its structure results 

 from a peculiar arrangement of arteries and veins similar to that which is found in the 

 penis, the clitoris, and female nipple. M. B. thinks, that the spleen very nearly resem- 

 bles the cavernous body, of the penis, both in structure and in its phenomena ; and he 

 considers it not only to consist of erectile tissue, but to be also the seat of a species of 

 erection more or less similar to that of the cavernous body. This viscus, he argues, pre- 

 sents an actual motion of expansion and contraction, and he adduces the three following 

 circumstances under which this takes place. 1st, In experiments ; when the course of 

 blood in the splenic vein is arrested in living animals, the spleen swells, but returns to 

 its former dimensions as soon as the circulation through the vein is restored. 2d, In 

 diseases ; the paroxysms of intermittents are accompanied with an obvious enlargement 

 of this viscus, which subsides as soon as the paroxysm is over. 3d, A similar phenom- 

 enon takes place during digestion. The lateral openings of the veins, noticed by Sir 

 Everard Home, seem to confirm the views of M. Beclard respecting the dilation and 

 frequent inosculations of the venous radicles in this viscus, which are common to it and 

 the other erectile tissues. (See the note in the appendix on the organs of Generation.) 



With respect to the functions of the spleen we will only adduce those views which 

 possess claims to a favourable notice. 



C. H. Schmidt, (Comment. dePathol Lienis.) considers that its vasa brcvia contribute 

 to nourish and strengthen the stomach; and that, as the blood of dogs deprived of the 

 spleen, is found to run speedily to putrefaction, it is concerned in, the preparation and 

 assimilation of the elements of the blood, and that it performs an office to the liver 

 analogous to that which the lungs fulfil with respect to the heart. 



Professors Tiedemann and Gmelin (Versuche uber die Verriclitnng der MHz, &c.*\ con- 

 clude, from their investigations on this subject, 1st, That the spleen is an organ closely 

 connected with the lymphatic system. This is shown by its being restricted to those 

 animals which possess a separate absorbent system, by the number of its lymphatic 

 vessels, and by the circumstance of the spleen of the turtle being similar to a mesen- 

 teric gland. 2nd, That a coagulating fluid is secreted in it from the arterial blood, is 

 taken up by the absorbents, and carried into the thoracic duct. This fluid or lymph, 

 they remark, was seen not only by them, but by Hewson ; and they conclude, that the 

 formation of it is the only means by whic"i it is possible to account for the use of the 

 great quantity of arterial blood which flows into the spleen. In answer to the ques- 

 tion, by what means this coagulable lymph passes into the absorbents ? they reply, 

 either there are, in the substance of this organ, particular gland-like bodies, and small 

 spaces or cells, which several anatomists say they have remarked, in which the fluid is 

 secreted and taken up by the absorbents, or the finest branches of the arteries in the 

 spleen pass immediately'into the absorbents, and by this means some parts of the arte- 

 rial blood reach the absorbents. From a consideration of all the facts obtained by 

 themselves and former investigators, they infer that a connexion subsists between the 

 splenic arteries and absorbents, either directly, or indirectly, by means of cells. The 

 secretion of this reddish coagulating lymph from the arterial blood takes place, in their 

 opinion, from the nerves h^ing excited, particularly during digestion : and consequent- 

 ly, by the plentiful secretion, the course of the blood is carried forward in the spleen, 

 which by this means is reduced in size. 3d, That this secreted coagulable lymph, when 

 conveyed into the thoracic duct is intended to render the chyle similar to the,f blood. 

 They consider this inference to be proved by at least two circumstances ; 1st, That 

 this change actually takes place, for the chyle of the thoracic duct differs from the 

 chyle of the mesenteric vessels, by a closer resemblance to perfect blood : 3d, That 

 when this coagulable matter was by any means prevented from reaching the thoracic 

 duct, this change did not take place. Amongst other proofs which Professor Tiede- 

 mann and Gmelin adduce in support of these circumstances, they show that the chyle 

 taken from the absorbents of the intestinal canal, before they had passed through the 



