DEVELOPMENT OE CIRBIPEDIA. 
141 
Tight, and that the lateral horns have nothing to do with the antennas of the Cypris. 
For what reason all these glands terminate in the two horns and their processes is 
another question, to which I can give no answer. The secretions of these glands during 
the Nauplins stage may be continually seen coming out of them; in the Cypris all 
these processes have been dropped, and the gland appears as a shell-gland ; and later, 
when the Cypris has fixed itself, this shell-gland, I think, is the one that furnishes the 
materials for the valves. 
The centre of the nervous system consists of two ganglia, which may be seen below 
the central eye, but which are often somewhat hidden by the upper part of the lip 
(Plate 13. fig. 18, cer). Above them, between the pigment-spot and the two feelers, 
there is a dotted band of a substance which might be nervous, but about the nature of 
which I am not able to give an opinion. 
Th e feelers (Plate 18. fig. 18, and Plate 14. fig. 22, x) consist of a basal joint, to which 
muscles are attached, and of a flexible upper one, into which a nerve goes. At their 
top I found no special terminating bodies, though I examined them repeatedly under 
high powers. These feelers are movable in a limited way. 
When the Nouplius has moulted for the seventh time, and the time for the meta- 
morphosis into the Cypris stage arrives, we see the large lateral eyes in the process 
of formation. At first they are a pair of roundish bodies (Plate 14. fig. 22, o ) reflecting 
the light and dotted with black pigment. Very soon the black pigment becomes more 
intense ; about eight lenses appear at their surface, and above each lens a cornea is 
formed. This stage is figured in fig. 23 for the southern larva, but is in our case so 
similar that I did not think it necessary to give another figure for it. However, it 
takes a long time to find a specimen among the largest larvae which have got these eyes, 
as they seem to throw off their Nauplial appendages as soon as the preparations for the 
metamorphoses are ready underneath. Among all the larvae which I examined I found 
only one in the stage figured on Plate 14 ; but I have no doubt that many might be 
discovered among the vast quantity of larvae which have been kept in our bottles. 
The organ y (Plate 14. fig. 23) is not, as may appear at first sight, a ganglion, but a 
patch of vesicular tissue, of which several may be seen in a specimen which has been 
killed in absolute alcohol and preserved in Canada balsam. The glandular substance 
in this specimen (easily recognizable from being more stained by carmine than the 
surrounding tissue) has been somewhat contracted, and patches of vesicles have appeared 
which clearly belong to a network of connective-tissue between the glands. 
The labrum , which in Plate 12. fig. 15 is represented as turned upwards, and in 
Plate 14. fig. 22 in the position in which the larva generally keeps it, is a very long and 
wide organ, being nearly two thirds of the diameter of the carapace in length. Its 
edges are very densely covered with small spines, and at the top there are invariably on 
each side two large spines. In older larvae, however, I frequently saw three spines 
(fig. 15), and in one case even four on both sides. It resembles on the whole very 
