THE GIANT EARTH-WORM OF GIPPSLAND. 33 
male opening, but is formed of the same small cubical cells. The oviduct leads down 
through the posterior septum of the thirteenth segment into the ventral body wall of 
the fourteenth. Its walls (Fig. 31) are composed of columnar ciliate cells, much more 
numerous than in the case of the vasa deferentia. The two ducts incline towards the 
median line, and open one on each side, very close together, in the middle of the 
fourteenth segment. They have no relation to the sete, opening in front of and 
to the ventral side of these. 
Though the testis and ovary closely resemble each other externally, sections at 
once show a great difference between the two. (Figs. 11 and 12.) At all times, so 
far as can be ascertained—certainly in winter, spring, and summer—the ovary 
contains large well-developed ova. A section through an ovary of a worm obtained in 
March is represented in Fig. 11, as seen under a magnifying power of 2,200 diameters. 
Only one of the projections from the central part is represented. The whole 
ovary has a diameter of rather more than 1 mm. The central part is composed, very 
much as the testis, of a mass of protoplasm, amongst which are muscle fibres and 
connective tissue serving as supporting structures (ct.) In the ovary ramify 
numerous blood-vessels (6v.) In parts outlines of cells may be distinguished, but as 
a rule the protoplasm forms an indefinite mass, in which many nuclei of various sizes 
are scattered. The smallest (0.’) are very minute, and resemble those in the testis 
stalk. Others, gradually increasing in size, are seen (0.* 0.2) Around these the 
protoplasm is difficult to distinguish, since it takes stain but slightly. Larger nuclei 
(0.’) lie further away from the centre of the ovary, and around them the protoplasm 
is becoming marked off into distinct areas, and also differs in its ability to take stain. 
In the nuclei the chromatin fragments are arranged roughly in a circle near to the 
external surface. At the extremities of the projections, the cells are still larger (0.’), 
and have the appearance of mature ova. These cells have undergone great growth, 
and their nuclei are very large and distinct, and generally spherical in shape. In the 
largest one, which forms the extremity of one projection, its inner end being buried 
deeply amongst smaller cells, the nuclear membrane can be distinguished, together 
with a nuclear network with chromatin fragments, and a somewhat eccentrically 
placed mass of chromatin, in which lies a still more darkly-stained portion. In the 
other large cells, owing doubtless to the different results produced by reagents, the 
chromatin appears distributed in various ways, but there is always one large main 
portion placed eccentrically, and besides this, there may be smaller fragments 
irregularly scattered. These ova grow in size, nutriment being possibly afforded to 
them by the absorption of the smaller cells at their inner ends, as well as by the 
numerous blood-vessels in the ovary, and when mature they fall into the ccelom, and 
enter the open ciliated end of the oviduct, which lies close beneath the ovary on 
either side. 
As far as development goes, a small number of cocoons have been secured, and 
I hope goon to be able to procure many more, and to work out the development 
F 
