94 MR. T. WHARTON JONES ON THE BLOOD-CORPUSCLE CONSIDERED IN 
Blood- corpuscles of the Earth-worm. 
40. The blood was most readily obtained for examination from the abdominal 
vessel, but in abstracting - it, care was required to guard against its becoming mixed 
with the secretion poured out from the skin in great abundance when the animal 
was wounded. 
41. The corpuscles of the blood of the Earth-worm are remarkable for their great 
size, being on an average TiV oth or x wo th of an inch in diameter. There are both 
granule and nucleated cells. 
42. Granule Blood-cells. — Of these there are both coarsely and finely granular 
stages. I have not observed the cell-wall of the granule-cell in the coarsely granular 
stage to shoot out into more than perhaps a single bud-like process (fig. 1.), but in 
the finely granular stage, the cell-wall shoots out into so many cilia-like processes, 
that the cell soon after the blood is drawn presents a stellate form (fig. 2.), the gra- 
nulous mass about TWo^h °f an inch in diameter occupying the centre. 
43. By the action of water the granule-cells become uniformly distended (figs. 3 
and 4.), the stellate form into which the cell in the finely granular stage had fallen 
disappearing. In this state of distention the cells measure i~ iV ot-h or y^-gth of an 
inch in diameter, but their granulous contents do not fill their whole interior. 
44. Acetic acid causes the granules of the cell in the coarsely granular stage to 
break up, but does not dissolve their substance. The granulous contents of the cell 
in the finely granular stage it renders more transparent. 
45. Nucleated Blood-cells.— Instead of perfect nucleated cells, the cells about to 
be described under this head might, perhaps, rather be said to be cells in transition 
from the granule-cell phase, inasmuch as the nucleus, though quite evident, is still 
surrounded by granular matter. 
46. The cells under consideration have always been collapsed when first seen, 
though the blood was examined as quickly as possible after being drawn ^ but I have 
observed them in the act of shooting out their cell-wall into processes (fig. 5.), like 
the granule-cell in the finely granular stage. 
47- By the action of water, the processes are made to disappear by the cell beco- 
ming uniformly distended. In this state the cell measures about y^g-gth of an inch in 
diameter, and in its interior is seen the cellaeform nucleus about - ^do th of an inch in 
diameter, with a finely granulous mass surrounding it (fig. 6.). This granulous mass 
is not dissolved entirely by acetic acid, but it is rendered more transparent. 
48. The red colour of the blood of the Earth-worm is, as is known, seated in the 
plasma, but it is to be remarked that some of the nucleated cells appear very slightly 
tinged, as also the nuclei, in their interior. 
49. Besides the nucleated cells now described, corpuscles are met with altogether 
like their nucleus and its surrounding granulous mass, both in form and size. 
50. Lastly, there are a few corpuscles like perfectly free nuclei, and a considerable 
number of elementary granules, the larger, of the form of biconcave circular discs. 
