178 ANNALS OF THE QUEENSLAND MUSEUM. 
pass below it. Calcareous corpuscles were not seen. The cortex 
occupies a much greater portion of the section than does the 
medulla. 
Genitalia. — The genitalia alternate irregularly. The pore is 
located on a very slightly projecting papilla immediately in front 
of the middle of the edge of the segment. The common cloaca is 
very shallow, the male aperture more frequently being placed just 
posteriorly to the female pore. However, the reverse position of 
the opening is not uncommon. Both are on practically the same 
dorso-ventral level, the vaginal orifice being sometimes slightly 
more dorsally situated than the male pore. The sex ducts lie close 
together in their outer portions, both passing between the excre- 
tory vessels and below the lateral nerve and the vitellaria of the 
corresponding side. 
The male glands are scattered to form two extensive testicular 
fields extending from near the anterior edge of the segment to the 
ovarian lobes, separated along the middle of the segment by a 
rather wide interval in which lies the uterus. Each field contains 
between 36 and 40 vesicles arranged more or less in a, single row, 
though all the glands do not by any means stand at the same 
level. Their arrangement in the parenchyma is figured in the 
transverse section in Fig. 3. It will be seen that they occupy a 
considerable portion of the medulla, and are as a whole almost 
equidistant from either surface. It was therefore a matter of some 
difficulty to fix the surfaces as dorsal and ventral respectively. This 
difficulty was increased by the absence of transverse excretory 
vessels by which one might identify the ventral vessels, and by the 
position of the ovarian lobes, which are placed on the same level 
as the testes. However, the ovarian bridge very closely approaches 
the opposite surface, which I have accordingly designated the ven- 
tral. The testes are about 0.05 mm. in diameter in surface view, 
their transverse (i.e., dorso-ventral) diameter being greater, reach- 
ing 0.082 mm. These glands are practically absent in the region 
of the genital ducts. The vas; deferens is a closely coiled wide tube 
lying at about the middle of the testicular field on that side of the 
segment which bears the genital pore. It frequently extends 
inwards as far as the mid-line, lying dorsally to the uterus. During 
sexual maturity the coils occupy in transverse section most of the 
