9(3 MR. T. WHARTON JONES ON THE BLOOD-CORPUSCLE CONSIDERED IN 
Mollusca. 
59. My examples of Mollusca are confined to the classes of Gasteropoda and 
Acephala, — from the former I have taken the Whelk ( Buccinum magnum), — from the 
latter the Mussel ( Mytilus edidis), in which to examine the blood-corpuscles. 
Blood-corpuscles of the Whelk. 
60. The shell having been broken to pieces from around the animal, the blood 
was readily obtained from the great vessels of the heart, or from the heart itself ; 
but notwithstanding every care in abstracting it, the blood was not always quite 
free from admixture with foreign particles, such as ciliated epithelium-cells and 
the like. 
61. Kinds of Corpuscles. — There were granule-cells and nucleated cells essentially 
similar to those of the blood of Annulosa. 
62. Granule-cells. — By the time the blood coukl be examined, the granule-cells 
had, for the most part, become agglomerated together in groups, and their cell-wall 
was seen already shot out into processes (fig. 1.). 
63. Both coarsely and finely granular stages of the granule-cell were to be recog- 
nised. 
64. The size of the granule-cell was on an average from -gwmBh 1° T oVo th of aa 
inch. 
65. By the action of water the cell became uniformly distended (fig. 2.), to the 
size of about as much as x 5 1 00 th of an inch in diameter and then burst, the cell-wall 
disappearing and leaving the granulous contents in a mass with the nucleus visible 
in the centre (fig. 3.). 
66. Nucleated cells. — Some of these were seen with the cell-wall shot out into 
processes (fig. 4.) ; some not (figs, 5, 6 and /.). 
67. Those cells of which the cell-wall did not shoot out into processes, were for 
the most part circular (figs. 5 and 6.) ; but some also occurred which appeared to be 
elliptical (fig. /•)> though these might have been circular cells seen somewhat raised 
up on edge. The cells under consideration often presented a finely granulous matter 
in their interior, and some were slightly tinged of a red colour. Their size was about 
2 sV oth °f an Mch diameter. 
68. Those cells of which the cell-wall shot out into processes, when uniformly 
distended by water, were larger, measuring about TbVo th of an inch in diameter 
(fig. 4 a.). 
69. The nucleus, oval or circular, and reddish in the interior, measured on an 
average from 4 §6 o th to 3 - 6 \oth of an inch, these being the means when the nucleus 
was oval. 
70 . Besides the corpuscles now described, there were a few like free nuclei, and a 
great quantity of elementary granules of different sizes, the larger biconcave and 
circular. 
