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J. STEPHENSON. 
marked off from the cells ; the periphery of the cell fades 
away into the intercellular substance, and in the measurements 
of the cells as given above, the reference is to the deeply 
staining portion only, on account of the impossibility of 
determining the limits of cell and intercellular matter. In 
amount this latter may be very considerable, and the staining 
portions of the cells are then comparatively widely isolated 
from each other. It has the character of a granular amor- 
phous matrix, into which the bodies of the cells merge, and 
through which some of the fibrillar processes of the deeper 
staining matter are continued. 
Transformation of the Cells. — The chroinophil cells 
in this species are more completely aggregated together on 
and behind the pharnyx than, for example, in Pheretima 
posthum a; the number of the cells which penetrate inwards 
amongst the interlacing muscular fibres on the dorsum of the 
pharynx is much smaller. The chromopliil cells which occur 
between the muscular fibres are mostly isolated, or in twos and 
threes; in them the densely staining matter becomes less in 
amount, the periphery of the cell may show a reticular 
structure, and the cell processes are distinctly fibrillar. At a 
further stage the deeply staining matter disappears ; the 
cell elongates to form a strand, the nucleus is at one.side, the 
pale-staining fibrillse form a reticulum. Longer strands 
appear, composed apparently of several cells, since they may 
contain one, two, or more nuclei. The nuclear changes are 
similar to those previously described; the nucleolus becomes 
smaller, and disappears or becomes indistinguishable from 
the chromatin grains ; the nucleus itself decreases in size, and 
becomes faint and difficult to distinguish ; appearances here 
again suggest that at this stage it sometimes divides ; ulti- 
mately it seems to disappear. 
The Capsule. — In the adult, a peritoneal capsule is 
present in parts over the main mass of the cells, especially 
posteriorly ; in other species also the posterior surface 
appears to be the region where a recognisable capsule is 
best developed. But it is absent in other parts, — perhaps in 
