32 ON THE ANATOMY OF MEGASCOLIDES AUSTRALIS, 
in the testis. Probably small masses of testicular cells break away from the testis, and 
in some manner are taken up by the vesicule seminales. The cells then separate 
from one another, and come to lie freely within the capsule. The great supply of 
blood-vessels is probably connected with the further development of the sperm cells, 
which increase greatly in size. Their nuclei divide, but so far as can be seen, the 
protoplasm of the cell does not do so. At first the nuclei, as in the figure in the left- 
hand corner (2), are somewhat spherical, and contain distinct chromatin spots. A 
later stage shows a number of oval dark-staining nuclei, arranged roughly round the 
periphery of a granular central mass of protoplasm. To this may now be given the 
name of spermatosphere. 
In certain of the spermatospheres, the nuclei take stain throughout, as in the 
figure. A somewhat later stage is to be found, in which processes of protoplasm 
project from the surface of the spermatosphere (sp.), each containing an oval nucleus, 
and in the latter the chromatin forms a crescent-shaped structure at the outer end—a 
curious stage corresponding to that already described and figured by Bloomfield as 
occurring in Lumbricus.* At this stage the central granular mass of protoplasm is 
clearly differentiated as the sperm-blastophore. Later on, the nuclei come to lie at 
the inner ends of the processes, and the protoplasm to gradually elongate into a 
pointed thread-like structure (sp.) At the same time, the developing spermatozoa all 
come to point in the one direction. Hach sperm element elongates, the nuclear 
end forming the head, the clear protoplasm the tail, and all the tails lie close together, 
so that the whole mass of spermatozoa forms a flame-shaped structure, in the broad 
end of which is the sperm-blastophore. When the former are mature, and ready to 
separate from one another, the latter cannot be detected, though possibly it is 
concealed from view by the elongate rod-shaped heads of the spermatozoa, which take 
the stain deeply. 
The ripe sperm comes finally to lie im the ccelom, probably either by discharge ot 
a capsule in which it is contained, or else by means of forcing its way through the 
capsule walls. There is no direct connection between the openings of the vasa 
deferentia and the seminal reservoirs, which are most largely developed in the three 
segments behind the one containing the second pair of openings of the male ducts. 
Within the vesicule seminales are, as usual, found capsules containing the 
embryos of a gregarine. 
2.—Female Organs. These consist of a single pair of ovaries attached to the 
posterior face of the septum, between the twelfth and thirteenth segments, close on 
either side of the ventral line. ach has externally much the same appearance as a 
testis, but the projections from the small central mass are rather more racemose than 
radiate. The open end of the oviduct lies close to each ovary (Figs. 3 and 4, od.), 
and has the usual ciliate funnel shape. It is somewhat smaller than the corresponding 
* Q.J.M.LS. 1880, 
