VASCULAR GLANDS LYMPHATICS NERVES. 221 



of the Splenic vein ; and it has been hence concluded by some, that they do 

 not constitute normal elements of the Splenic parenchyma, but that they are 

 either contained in its capillaries, or, if actually diffused through the pulp, 

 are so as a result of an abnormal extravasation. These conflicting views 

 may be reconciled, if, as stated by Mr. Gray and W. Miiller, the splenic 

 blood, in its passage from the arteries to the veins, ordinarily escapes from 

 the walled vessels into indefinite channels traversed by connective tissue, so 

 that its corpuscles may become diffused through the parenchyma without 

 any departure from its regular course; and it is a confirmation of this view, 

 that the amount of colored corpuscles in the spleen-pulp augments with the 

 general turgescence of the vascular system, and diminishes with the pov- 

 erty of the blood, so that in animals reduced by ill-feeding, it disappears 

 altogether. 



iv. The Lymphatics of the Spleen are few and inconsiderable in Man ; 

 being less numerous than in other glandular organs, such as the liver and 

 kidneys. In some of the lower animals, as in the horse, 1 they are more 

 abundant, and form two systems, one of which may be followed into the 

 interior of the organ acompauying the larger arteries and veins, and invest- 

 ing the smaller vessels with a distinct sheath, between which and the parietes 

 of the bloodvessels numerous lymph-corpuscles may be found, whilst the other 

 forms a plexus in the trabeculav 



V. The Nerves of the Spleen are apparently very large in some animals, 

 especially in the Ruminants; but the great size of their trunks and branches 

 is chiefly due to the large proportion of ordinary fibrous tissue which enters 

 them ; the number of real nerve-fibres being extremely small. 



vi. The chemical composition of the Spleen is indicated by the following 

 analysis of Oidtmann : In 1000 parts were, water, 750.31, solid residue, 

 249.69 ; of the latter, 242.32 parts were organic substances, and 7.37 inor- 

 ganic. Amongst the organic substances, albumen, fats, inosite, lactic, formic, 

 succinic, acetic, butyric, and uric acids, sarkin, xanthiu, leucin, pigment, 

 and much cholesteriu have been distinguished. The most remarkable cir- 

 cumstances respecting the inorganic constituents are the large relative quan- 

 tity of soda salts and of oxide of iron. 3 From the observations of Mr. Dob- 

 sou, 4 which have been corroborated by other observers, it appears that the 

 Spleen attains its maximum volume at the time that the process of chymi- 

 ficatiou is at an end, namely, about five hours after food is taken ; and that 

 it is small and contains little blood seven hours later, when no food has been 

 taken in the interval. The removal of this organ from the body has been 

 performed even in man without serious effects ; whilst in some instances in 

 animals perfect regeneration has occurred, which is probably attributable 

 to the hypertrophy of the little splenculi so often present in the immediate 

 vicinity of the Spleen ; 5 in others, enlargement of the lymphatic glands in 

 various parts of the body, as the neck and axillte, have been observed. 

 Maggioraui 6 noticed a deficiency in the amount of iron contained in the 

 blood-corpuscles; and in the dogs operated on by Dr. Dalton 7 an unnatural 

 appetite and ferocity of disposition were exhibited, which may perhaps be 

 attributed to imperfect assimilation of the food they consumed. 



158. The history of the development of the Spleen, which was studied with 



1 See Tomsa, in Sitz. d. k. Akad. zu Wion, Bd. xlviii. 



2 See Kyber, in Max Sohulte's Archiv fur Mikroscop. Anat., Bd viii, 1872, p. 568. 



3 v. Gorup-Besanez, Phvsiolocj Chemie, 1862, p. 660. 



4 Lond Med. and Phys. Journ., Oct. 182 >. 



5 Phillipeaux and Mayer, C Rendus". 1861, p. 547. 



6 Comptcs Pvendus, 1861, p. 319. 7 Human Physiology, 1871, p. 203. 



