^- Royal Society 



corpisctes;^ ^HeieJie distinguishes as the phases, first of the i7min 

 nule blood-cell, which he describes as a cell filled with granules, dis-ii 

 closing by the solvent action of dilute acetic acid on these grjuiules 

 a vesicular, or as the author terms it, a " celltpform" nucleus. These! 

 granule cells appear under two stages of development, namely, thei 

 qoarsdy granuloua stage and the finely granulous stage. The se- 

 cond phase is that of the micleolated blood-cell, oval in shape, con- 

 taining a vesicular (or " cellseforni ") nucleus, and red-coloured mat- 

 ter. These cells likewise appear under two stages of development; 

 colourless in the first and coloured in the second, in which last stage 

 it constitutes the red corptiscle. In the early mammiferous embryo,' 

 he finds, in addition to the former, a third phase, that of free vesicu'- 

 lar nucleus, exhibiting, like the nucleplated cell, the colourless v^^< 

 the coloured stages. i;j,tt:.ilij U'H\n'^•■'.^:n) oii; aJa3iim.'>qz9 



On examining the corpuscles of the lyrfiph»of (vbriebrate'arBima)^^ 

 the author finds them in all the classes to be identical in structure 

 with their blood-corpuscles, and diftei-ing only in the inferior degree? 

 of coloration attending their last stage. In the oviparous classes, \\& 

 observes that the nucleolated are more numerous than the granule 

 cej Is, while in the mammifera the latter are predominant, which is 

 the reverse of the proportion in which they exist in the blood of 

 these animals. He finds that some of the nucleolated cells of the 

 contents of the thoracic duct exhibit a marked degree of coloration, 

 and have an oval shape ; thus offering a resemblance to the blood 

 of the early embryonic state. . . :;,ij 



' The blood-corpuscles of all the invertebrate animals in which ;th*i 

 author examined them, present the same phases of granule and 

 nucleolated cells as in the higher classes, except that in the last 

 stage of the latter phase the coloration is very slight, but the vesi- 

 cular nucleus is frequently distinctly coloured. As in the higher 

 classes, corpuscles exist in diff'erent states of transition from the gra-- 

 nular to the nucleolated form of cell. In some of the invertebrata, 

 corpuscles are found which appear to be the nuclei of some of the 

 imcleolated cells become free ; and these the author considers to be 

 abortions, rather than examples, of cells having attained their third 

 phase of free cells. Corpuscles are also met with in these animals^ 

 in greater or less abundance, belonging to the lowest forms of or- 

 ganic elements, namely, elementary granules. 



■ ' The comparison which the author institutes between the blood- 

 corpuscles of the vertebrate and invertebrate divisions of the animal 

 kingdom, tends to show that they in all cases pass through similar 

 phases of development, except with respect to the last, or coloured 

 stage of the nucleolated cell, which they do not attain in the lower 

 classes of animals. He finds that the blood-corpuscles of the crab, 

 according to an analysis made by Professor Graham, contain a sen-! 

 sible quantity of iron, perhaps as much as red corpuscles. He con- 

 siders the corpuscles of the blood of the invertebrata, inasfar as re- 

 lates to the absence of nucleated cells, as resembling those lof-tiiB 

 lymph of vertebrate animals. /i::i.! 



bicu5«iOn some peculiar modifications of the Force-pf Cohesion, with 



