232 D. J. SCOURFIELD ON EPHIPPIA OF LYNCEID ENTOMOSTRACA, 



line of c'hitin as is usually the case. Over the darkened area the 

 chitin is minutely pitted. The ventral margin is bounded by a 

 line of loosely connected pieces of chitin, which have apparently 

 been produced independently of the ordinary shell markings, and 

 it cuts the old ventral edge of the shell just in front of the 

 posterior ventral angle. I have not been able to satisfactorily 

 demonstrate the existence of this line of special cells in the 

 ephippial female before moulting, but I think, from what we 

 have seen in other cases, that we may assume it to exist. The 

 inner membranes enclosing the egg are very delicate, and cannot 

 be traced \vith certainty in all cases completely round the egg. 

 They sometimes project from the posterior part of the ephippium. 

 I have, at times, seen many of these ephippia attached to the 

 sides of the bottle in which the species has been kept. 



Alonella excisa (Fischer). 

 This is one of the very minute ephippia, scarcely exceeding 

 yJq in. in length. It is very much darkened, but otherwise the 

 shell does not show much modification, for it is but very slightly 

 thickened at the back, and the ordinary surface reticulations, with 

 their characteristic secondary markings, are practically the same 

 ^s in the ordinary female (see Fig. 23). I do not know whether 

 the line of separation between the ephippium and the ventral 

 parts of the shell is entirely produced by a line of loosely 

 connected cells or not, for the ephippial female has not been 

 examined, and in the ephippium the ventral margin is remarkably 

 shai'p and regular, only showing posteriorly a ragged edge. The 

 line meets the original ventral margin of the shell just in front 

 of the posterior ventral angle. There lis a great mass of mem- 

 branous material of a delicate character surrounding the egg, 

 which may even protrude from both the anterior and posterior 

 ends of the ephippium. In one specimen, which I rolled about in 

 the live-box so as to open the valves and expose the egg, the 

 membranes seemed to be still attached posteriorly to the inner 

 surface of the shell. As in the case of the foregoing species, I 

 have observed many of these ephippia attached to the sides of a 

 glass jar in which the animals were contained. 



Alonella cliaphana (King). 

 Professor Sars obtained ephippial females among the specimens 

 of this species raised by him from dried mud from Argentina, 



