92 MR. T. WHARTON JONES ON THE BLOOD-CORPUSCLE CONSIDERED IN 
which I obtained the blood was the same as that already stated in regard to the 
Crab and Lobster, viz. by snipping off one of the legs and receiving on a plate of 
glass the minute drop of blood which oozed out. 
22. The blood-corpuscles of the Spider are almost identical with those of the Crab 
and Lobster. There are both granule-cells and nucleated cells, — the latter the more 
numerous, — which when examined immediately on the blood being drawn from the 
animal, present, the former an oval, the latter an elliptical shape (figs. 1, 2 and 7-)- 
These shapes, however, are in general soon lost. The cells become roundish, their 
cell-wall at the same time shooting out into processes. This shooting-out of the cell- 
wall into processes is more especially presented by the granule-cells (fig. 3.), for in 
the case of the nucleated cell, it might be said that the cell-wall in general rather 
becomes shrivelled and collapsed than shoots into cilia-like processes (fig. 8.). 
23. The size of the corpuscles is much the same as in the Crab. 
24. There are both coarsely and finely granular stages of the granule-cell (figs. 1 
and 2.), and also cells in transition from the granule to the nucleated phase. 
25. By the action of water, the cell-wall of both granule and nucleated cell is dis- 
tended and brought out in the same way as in the case of the blood-cells of the Crab 
(figs. 4, 5 and 9.), and by the action of acetic acid the granules of the granule-cells 
are broken up and dissolved, leaving the nucleus exposed (fig. 6.). 
26. In regard to a coloured stage of nucleated cell, what was above said in the 
case of the Crab (par. 16.), is applicable here. 
27- As in the blood of the Crab also, a few elementary granules are seen floating 
about. 
Examination of the Blood-corpuscles of Insecta. 
28. In entering on the examination of the blood-corpuscles of insects, the advan- 
tage of having first examined those of Crabs and Spiders is strongly felt ; for the 
blood of these animals being readily and certainly obtainable free from admixture 
with foreign particles, which might be confounded with blood-corpuscles, the cha- 
racters of their blood-corpuscles will serve as a guide by which to recognise then- 
analogues in the blood of insects and other invertebrate animals, the conformation 
and structure of the bodies of which are such that we cannot be sure that the blood 
obtained from them is quite free from foreign admixture. 
29. As examples of perfect insects I have taken Beetles, and as examples of chry- 
salises I have taken those of the Cabbage Butterfly*. 
Blood-corpuscles of Beetles. 
30. The matter examined as the blood of these insects was the clear greenish 
* I have also examined the blood-corpuscles of the Caterpillar, and found them in essential particulars the 
same. Having, however, as yet obtained but one specimen of a caterpillar of the Cabbage Butterfly, I am not 
able to give here a description and delineation of the blood-corpuscles. This, however, I shall be able to do on 
another occasion. 
