D. J. SCOURFIELD ON EPHIPPIA OF LYNCEID ENTOMOSTRACA. 225 



iihe crumpled membranes forming the capsule are produced by 

 a special modification of the inner lining of the shell valves is 

 evident from an examination of the back of an ephippial female, 

 which shows a very gi-eat development of the inner layer of 

 skin, as indicated in Fig. 8. This figure also shows the great 

 increase in the thickness of the chitin at the back of the shell. 



In living specimens of the ephippial female of A. karjxie a 

 line of weakness very similar to that already referred to in 

 connection with C. rectirostris can, with care, be traced, 

 and under a high power it can be shown to consist of a i-ow 

 of cells, or rather pieces of chitin, which are only loosely joined 

 to the rest of the shell and to one another. 



Alonopsis ambigua Lilljeborg. 



I am indebted to Professor Sars for ephippial females and 

 moulted ephippia of this species, the particular specimens sent 

 coming originally from Algeria. The ephippium is shown in 

 Fig. 9, and it will be noticed that quite a third of the ventral 

 portion of the shell has been detached. A line of weakness is 

 evidently formed in this case before the moulting of the ephippium, 

 .for there are still to be seen a few of the loosely-connected pieces 

 of chitin along the ragged ventral margin. The outer shell 

 structure is not modified, for the excessively fine longitudinal 

 striae on the surface are still to be seen on the ephippium, but 

 there is the usual thickening of the shell along the dorsal margin. 

 Within the outer shell, however, there is a dense mass of 

 chitinised cellular material occupying a quite definite area, and 

 closely investing the egg. This material, which seems to serve 

 as " packing " for the egg, is composed mainly of cells of various 

 sizes (Fig. 10), the larger ones for the most part being along the 

 back, while just over the egg itself the cellular nature of the 

 material seems to change into a mass of minute fibres felted 

 together. The " packing " can be seen in the ephippial female in 

 the process of being produced from the inner lining of the carapace, 

 and no doubt it is homologous to the delicate membranes seen in 

 Camptocercus, and to the membranous capsule in Acroperits. 



The appearance of this ephippium is, if we confine our attention 



to the portion occupied by the " packing," strikingly similar to 



"that of the Daphnid Simocephalus vetuhcs, but the cellular 



'" packing," although giving this ephippium such a decidedly 



