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



In my paper on the Winter egg of Leydigia acanthocercoides 

 (10) I referred to the principal sources of our knowledge of the 

 ephippia of the Lynceidae, but it will probably be useful if the 

 same information is repeated here, together with a few additional 

 references to the Hterature of the subject — which is, as ah-eady 

 hinted, very meagre. 



The first allusion to ephippia and winter eggs among species 

 of the Lynceidae, so far as I have been able to discover, is made 

 by Jurine in his classic work " Histoire des Monocles" (2), 

 published in 1820. He only refers specifically to Chydorus 

 sphaericus, the development of which he figures on Plate 16 from 

 the egg, " jusqu'au moment oii se forme la selle," etc. In figs. 

 Syand 3 ^ on the Plate mentioned he shows an ephippial female 

 seen from the back and from the side, and in 3 A a moulted 

 ephippium with its egg. Generalising apparently from this 

 particular case, he says, when considering the characters of the 

 group to which Chydorus belongs : '• Ces petits monocles nous 

 oftrent encore une autre particularite. La selle qui couvre leur 

 dos ne contient jamais qu'une seule boule, laquelle est placee au 

 milieu de cette pellicule noire et y fait saillie." He goes on, 

 however, to admit that perhaps in the larger species, normally 

 carrying numerous eggs, the statement just quoted might 

 not hold good. 



The next reference to ephippia of Lynceidae that I have 

 seen is to be found in a very elaborate paper by Schodler (7), 

 published in 1846, on Acanthocercits rigidus {^=Acantholeherls 

 curvi7'ostris). It is stated that in this species, and also in the 

 Lynceidae, the whole of the valves, which moreover are said not 

 to suffer any noticeable alteration, are usually employed to retain 

 the winter eggs. The whole " Eierpacketchen " is thrown off at 

 the next moult, and attached to plants or to the walls of the 

 vessel containing the animals. It is also incidentally noted that 

 the number of eggs in the ephippium of Eurycercus lamellatiis 

 (the only Lynceid mentioned by name) varies from two to ten. 

 Many years later (1863) Schodler issued another paper (8) in 

 which he refers to the winter eggs and rudimentary ephippia 

 of Eurycercus lamellatus, Peratacantha truncata, and Chydorus 

 sphaericus, and he again notices that these Lynceid ephippia 

 are often attached to plants, etc., as in the case of Acantho- 

 leheris. 



