CHAP. XXVII ] THE COLOURLESS CORPUSCLES. 303 



are generated in the liver, as first pointed out by Weber, and in 

 the mesenteric and lymphatic glands, and from these sources sup- 

 plied to the blood. In this fluid 

 they under go a trans formation into 

 the completely formed blood-cor- 

 puscles, by the removal of the 

 granules, the increased develop- 

 ment of the nucleus, and the 

 generation of colouring matter, 



excepting in the mammiferOUS Granules> granule-cells, and red blood-corpus- 



rwr-Yvncoloa wTineo nHiTnaff rlinno-p clesfrom the embryo chick at the twentieth day of 



COrpUSCleS, Whose Ultimate Change incul)ation . a Of Granules some being enveloped 



cf^m* fr> rnncicf in +TiP rwmnlpfp by a faint cell-wall, and granule-cells with coarse 



seems to consist in tne compie e granules . b bi red biood-corpuscies. Mag. 200 

 absorption of the nucleus, accord- diam> 



ing to Kolliker, or the removal of the wall of the cell, according 

 to Wharton Jones. 



Now as there can be no doubt that, in the adult, the lymphatic 

 and chyliferous systems afford a source for the constant develop- 

 ment of particles identical with the colourless corpuscles, and as such 

 corpuscles are always found in considerable proportion in the blood 

 (being more numerous under circumstances unfavourable to normal 

 changes, as in inflammations), it seems very reasonable to infer that 

 similar transformations of colourless into coloured particles are going 



Fig. 182. Fig. 183. 



a. Granules of which the cell- Nucleated cell (a), red corpuscles (6), and 



wall is not visible, b. Granule- granules from the chick on the 20th day of 



cells and red corpuscles. Mag. incubation. Mag. 200 diain. 

 200 diam. 



on in the adult as in the embryo, and that the lymphatic and lacteal 

 systems must be at least one, and that a fertile source, from which 

 red corpuscles are being continually supplied to the blood. 



If, however, we reject this view of the relation of the colourless 

 to the coloured corpuscles, then we must regard them as inde- 

 pendent particles, each having its special function, and it devolves 

 upon the advocates of this view to suggest the office, and to explain 

 the mode of origin and decay of each. 



