D. J. SCOURFIELD ON EPHIPPIA OP LYNCEID ENTOMOSTRACA. 221 



ephippium contains but a single winter egg. I have not 

 been able to obtain moulted ephippia of tliis species, but from 

 the drawing given by Weismann (12, Taf. vii., Fig. 10), repro- 

 duced in Fig. 2, it will be seen that a large part of the ventral 

 portions of the valves break away from the ephippium in a 

 manner which we shall find to occur again and again as we proceed. 

 Whether there are any special inner membranes surrounding 

 the eggs, as in most, if not all, other Lynceid ephippia, I do 

 not know, but it is at least very probable. 



Camjytocercus rectirostris Schodler. 



I have been able to examine the moulted ephippium of 

 this species on several occasions ; and as, owing to its thinness 

 and transparency, it is a particularly favourable object for 

 investigation, and moreover seems to bring out many of the 

 essential features of a Lynceid ephippium, it will be well to 

 devote some extra care to its examination. The ephippium 

 is shown in Fig. 3, and it will be seen at once that it consists 

 of the moulted shell, minus a rather considerable portion of 

 the ventral region. If we commence by looking at the four 

 edges of the ephippium, we notice that the dorsal and posterior 

 margins are of exactly the same contour as seen in the shell 

 of the ordinary female of this species ; but while the latter 

 is unmodified, the dorsal margin is very considerably thickened 

 by a deposit of clear homogeneous chitin. We shall find that 

 this increase in the thickness of the chitin along the back 

 is probably a universal characteristic of Lynceid ephippia, 

 and I further believe it is a feature common to all ephippia. 

 The anterior edge is formed by the line of junction between 

 the head-shield and the valves, as may readily be proved by 

 comparison with an ordinary moulted shell. The little up- 

 turned cusp at the dorsal end of the anterior edge is very 

 characteristic, and may prove to be peculiar to the genus 

 Camptocercus, although it is faintly foreshadowed in Acroperus. 

 The ventral margin of the ephippium, unlike the others, is 

 somewhat jagged in appearance. It runs approximately 

 parallel to the dorsal line for the greater part of its length, 

 but posteriorly it turns towards and eventually cuts the 

 original ventral margin of the shell just above the posterior 



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