54 ON THE ANATOMY OF MEGASCOLIDES AUSTRALIS, 
divides into the two commissures. Only one giant fibre (g./.) is present so far 
forwards. 
Fig. 11.—Section through a single one of the numerous racemose projections 
from the surface of the ‘ovary. The upper end of the figure represents the part 
attached to the body of the ovary, and consists of a syneytium—a mass of protoplasm 
not defined into cells, and amongst which numerous nuclei are scattered. The nuclei 
are of various sizes—o’, 0*, 0°, o°—with well-marked chromatin fragments, usually, in 
the above, arranged peripherally. The more highly-developed ova lie on the outside 
(o’), and contain large and very distinct nuclei, with nuclear membranes, and one 
especially large mass of chromatin. The end of the projection is occupied by a single 
mature ovum, with large nucleus inside, which is a network and a large mass of 
chromatin, smaller chromatin fragments being scattered through the nucleus. 
ZuIss, apo. obj. 2°0 mm. Ocular compens. 18. Magnifying power 2250. 
Fig. 12.—Section through one of the projecting rays of the testis. The whole 
structure 1s a syncytium, amongst which are blood-vessels and numerous strands of 
connective tissue and muscles. The nuclei are of different sizes, the smallest, which 
are very minute, being placed in the stem. Sometimes, a line of demarcation can be 
seen around one or two of the larger nuclei, as in Fig. 12a. The little mass of 
protoplasm measured ‘05 mm., and included two nuclei. Zxiss, apo. obj. 2°0 mm. 
Ocular compens. 18. 
Fig. 13.—A single seta, showing the slightly swollen internal end, to which 
muscles are attached. The swelling one-third from the free tip and the pointed free 
end. The setz are very small, and the one figured measured 5 mm. in length. 
Fig. 14.—Represents a diagrammatic longitudinal vertical section through the 
body, to show the relationship of the septa to the external markings of the segments. 
The left is the anterior end, and the septa are inserted behind the line indicating 
externally the boundary of the segment. A result of this is that dorsally the septa 
are pouched in the middle line, into which opens the dorsal pore, which always lies in 
the line of division between the segments (d.p.) 
Fig. 15.—A capsule of the vesiculze seminalis, in which are represented the various 
stages of development of the spermatozoa seen in the organ at the same time, though 
not necessarily in the one capsule. The figure, though showing structures, each of 
which exists, as represented in the vesicule seminalis, is hence diagrammatic, 
3 shows a mass of cells not long ago split off from the testis. 1 shows the separate 
cells. 2 show the increase of nuclei without corresponding division of protoplasm 
and separation into separate cells. Sf. show various stages in the development of 
the spermatospheres, the developing spermatozoa being attached to the central 
sperm-blastophore. Sperm. shows a mass of fully-developed spermatozoa, with their 
deeply staining rod-shaped heads massed together, doubtless around a sperm- 
blastophore at one end, and their tails, forming a flame-shaped structure, at the other 
