240 
It may be useful to future workers in this field to note here some 
of the points which need special attention in determining the various 
species of Cyclops. 
1. The number of joints in the anterior antennae and the length 
of the limb relatively to the body of the animal. 
2. The numbers of joints in the rami of the four pairs of natatory 
feet. 
3- I he characters of the rudimentary fifth pair of feet. 
4. The characters and proportional length of the caudal rami. 
The general outline of the body and its various segments should 
be noted, and in living specimens the colours of the body and egg- 
sacs may provide useful characters. 
Dr. Dalziel s attention seems to have been almost entirely directed 
to the Cyclopidae as being probably the intermediate bearers of 
human parasites, but it is quite likely that these hosts might also be 
found among the Ostracoda. In two, at least, of the British species 
of that group I have myself found scolices of an undetermined 
species of 1 aenia, and in yet another Ostracod many specimens of 
a larval 1 rematode worm, as well as a fully developed worm 
belonging to the group Acanthocephala. A brief reference to these 
may be found in my paper on the British species of Candoninae. 
(Proceedings of the Zoological Society of London, 1910, Part 1.) 
COPEPODA 
Cheops nigeriae, n. sp. Plate XVIII, figs. 1-;. 
Female, length o 88 mm. Body r robust (fig. 1), cephalic segment 
as broad as long, rounded and slightly produced in front; the two 
ollowing segments expanded laterally and obtusely angulated 
ehind; last thoracic segment very small; urosome rather short and 
stout, about one-third as long as the anterior portion of the body; 
t,enital segment moderately dilated; caudal rami as long as the 
umte lengths of the last two segments, slightly tapering distall}'. 
seta of the outer margin attached rather behind the middle, apical 
rf 6 ? n§ '’ thC lnnermost considerably longer than the entire urosome 
fl ^ nter * or ant ennae (fig. 4) eleven-jointed, reaching when 
? T <e , t0 thc midd,e of tlle second body-segment, rather sparingly 
0 e with setae of moderate length. Natatory feet short and 
