D. J. SCOURFIELD ON EPHTPPIA OF LYNCEID ENTOMOSTRACA. 219 



In passing, it may be remarked that Baird, in his " Natural 

 History of the British Entomostraca " (1), published in 1850, 

 quotes Jurine as to the occurrence of ephippia in the Lynceidae, 

 but states that he himself had never seen such structures in this 

 family. 



Nothing further appears to have been done on this subject 

 until Kurz, in 1874, published his " Dodekas neuer Cladoceren " 

 ^3), in which he definitely recorded the existence of winter eggs 

 in about sixteen species of Lynceids. He roundly declares that 

 a true ephippium is produced by the majority of the Lynceidae. 

 His descriptions are almost invariably very short, but he gives 

 a fairly long account of the ephippial female of Chydorus 

 sphaericits, and he also notices the fact that the ephippia are 

 attached to some solid body, such as the glass sides of the 

 aquarium. 



Weismann was at this time also working diligently at the 

 Oladocera, and among the numerous observations mentioned in 

 the "Beitrage zur Naturgeschichte der Daphnoiden " (12) he 

 refers to the winter eggs and ephippia of seven species of 

 Lynceidae. He seems to have been the first who paid any 

 close attention to the moulted ephippium, for he remarks that 

 the ventral margin of the valves separate from the thicker and 

 darker part of the shell, so that only this modified portion is 

 left as a covering for the egg, and he states that the process 

 is evidently a step in the direction of the typical ephippium 

 formation as found in the Daphnidae. 



In two of his papers on exotic Entomostraca — from Australia 

 (5) and South America (6) — Sarshas given figures and descriptions 

 of the ephippial females of various species of Lynceids, but has 

 not specially alluded to the ephippia in their detached condition. 



The recent beautiful work on Swedish Cladocera by Lilljeborg 

 (4) refers to the occurrence of winter eggs and the darkening 

 of the shell in ephippial females of many species of Lynceidae, 

 including some cases which had not j^reviously been recorded, 

 but it does not add anything to our knowledge of the structure 

 of Lynceid ephippia. 



To the foregoing account of the work that has so far been 



done on this subject may be added that in an article on Chydorus 



sphaericits, published in 1898 (9), the author of the present 



. paper made some observations on the ephippium of that species. 



