ELABORATION OF CHYLE AND LYMPH. 425 



remains in this state. This change takes place in the true coagulum also, if it 

 be kept moist for a sufficient length of time. The Chyle from the Recepta- 

 culum and Thoracic Duct coagulates quickly, often almost instantaneously ; 

 and few or none of the corpuscles remain in the serum. 



565. It is to be remembered that the Lacteals are the Lymphatics of the 

 intestinal walls and mesentery ; performing that function of Interstitial Absorp- 

 tion, which is elsewhere accomplished by vessels that are not concerned in the 

 introduction of alimentary substances from without. During the intervals of 

 digestion, they contain a fluid which is in all respects conformable to the 

 Lymph of the Lymphatic trunks. The aspect of the Lymph greatly differs 

 from that of the Chyle, the former being nearly transparent, whilst the latter 

 is opaque or opalescent ; and this difference is readily accounted for, when the 

 assistance of the microscope is sought, by the entire absence from the Lymph 

 of that molecular base which is so abundant in the Chyle, A considerable 

 number of corpuscles are generally present in it ; and these seem to corre- 

 spond in all respects with the white or colourless corpuscles of the Blood ( 577). 

 Their amount, however, is extremely variable ; as is also that of the oil-glob- 

 ules, which sometimes occur, whilst in other instances none can be discovered. 

 Lymph coagulates like chyle ; a colourless 61ot being formed, which encloses 

 the greater part of the corpuscles. 



560. The nature and source of the peculiar globules of the Chyle, are as yet 

 matters of doubt; some light, however, has been thrown on their history, by 

 recent investigations ; and much may be said of them, which, if not absolutely 

 proved, can scarcely be regarded as improbable. The process of their forma- 

 tion bears a striking analogy to that of the cytoblasts of Plants, as observed by 

 Schleiden ( 557). They appear in the midst of a fluid crowded with minute 

 granules, and appear to be themselves at first composed of an aggregation of 

 smaller particles. Various stages of development present themselves, how- 

 ever, in these bodies ; and the larger ones, which are chiefly to be met with 

 in the Thoracic Duct, are evidently cells, bearing a strong resemblance to the 

 Lymph-corpuscles, and to the Colourless corpuscles of the blood. Like the 

 latter, they contain three or four large central particles, which are distinctly 

 brought into view, when they are treated with acetic acid. Their diameter, 

 too, is about the same ; being usually between the 1 -2600th and the 1 -2900th 

 of an inch, or rather larger than the Red corpuscles of Human blood. It will 

 be hereafter pointed out, that there is strong reason to believe their functions 

 to be the same ( 578). 



567. The changes which the Chyle is observed to undergo, in its passage 

 from the Intestinal villi to the Thoracic Duct, suggest some inferences in regard 

 to the possible transformation of Fatty matter into a Protein-compound. That 

 the Chyle-corpuscles are not identical in chemical composition with the Mole- 

 cular base is quite certain, from the completely different effects of re-agents 

 upon the two respectively; but it maybe surmised that, as they appear to 

 consist of an altered form of Albumen, the soluble Albumen and the Fatty 

 matter are both concerned in their production. It has been stated that, whilst 

 the Fibrin increases, the Oil-globules undergo an evident diminution ( 564), 

 and that the quantity of Albumen lessens. It is not conceivable that the 

 Fibrin should be at once formed at the expense of the Oil-globules ; since 

 Albumen, which is a mere chemical compound, ready to undergo organization 

 and vitalization, is always the preceding grade. The Fibrin must, therefore, 

 be produced at the expense of the Albumen ; whilst new Albumen is elabo- 

 rated from the Oily matter. Of the process by which the latter important 

 change is accomplished, we are yet entirely ignorant ; but the evident altera- 

 tion which takes place in the proportion of azotized ingredients would seem to 

 show, that Nitrogen is in some manner communicated to the Chyle during its 



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