Coss—Nematodes, mostly Australian and Fijian. 265 
forms a shoulder in the cardiac region. Eye spots are unknown in the genus. 
The oblique nerve-ring encircles the cesophagus just behind the median bulb. The 
ventral excretory pore lies somewhat behind the nerve-ring. Lateral organs have 
been observed in but few of the species but this is doubtless due to insufficient care in 
observation; no doubt they exist in all the species. Where they have been observed 
they have been found to be placed opposite the pharynx and to be more or less elon- 
gated or elliptical in form and to have their long diameter placed longitudinally. 
In one species a glandular organ seems to exist in the cesophagus and to empty in the 
neighbourhood of the dorsal tooth. The intestine is usually thin-walled and ends in 
a rectum of the usual conoid form, 
The female sexual organs are usually double, symmetrical and reflexed, but 
in two species are single and reflexed. The tail is invariably conoid and is usually 
exceedingly slender in its posterior part. Caudal glands of the usual form are 
absent, there being no terminal pore or spinneret. There are, however, on the 
tail of both sexes, commonly in front of its middle point, two lateral pores, one 
on either side, which are in my opinion the outlet of unicellular glands situated 
near the anus. These pores and glands exist also in the genus /hadditis. 
Whether they are the morphological equivalents of the tail-glands in other genera 
I am not certain. It would seem that they cannot at any rate serve the same 
purpose as the ordinary arrangement as exhibited in Péectus and many other 
genera. The male has but one testicle, which is invariably reflexed near the 
extremity. The two arcuate spicula are equal in size and are elongated or linear 
‘and generally acute. Their proximal ends are usually cephalated by expansion ; 
accessory pieces parallel to the spicula are usually present. The peculiar papilla 
found on the tail of the male are divided into three groups of three each, a grouping 
first made plain through the observations of Dr. Biitschli. The full complement of 
papille is not always present, or at least has not always been made out ; when how- 
ever one or more pairs are absent, their position appears simply to stand vacant, and 
their absence does not much affect the position of those remaining. The first group 
may be described as the pre-anal group, and its members are ventrally submedian, or 
the posterior one may be lateral; they are situated opposite to, or in the neighbour- 
hood of, the spicula. The second group is post-anal and the members of it are often 
more widely separated than those of the pre-anal group, the anterior pair being 
usually ventrally submedian or even subdorsal. The posterior pair of the second 
group frequently lies farther back than the papille of the third group. The latter, 
also post-anal, are placed close together on the submedian line near where the tail 
diminishes most rapidly in size. In shape the papillee resemble hairs, and, in fact, 
may be such, but with a special function. Those of the third group, however, 
are different, being often more like ordinary papille in structure. No other 
KE 
