Description of Two Now Phyllopoda. 17 



muscle of the shell occurs, aud behind it the shell-gland 

 extending obliquely downwards. The latter is constructed 

 in exactly the same manner as in the European Limnadià 

 lenticularis, Lin., though somewhat narrower and lingui- 

 form in outline. 



The semipellucid shell admits of the enclosed animal 

 being faintly traced through it (see fig. 1); but in order to 

 examine it more closely in its natural situation, it is neces- 

 sary to remove carefully one of the valves, leaving the ani- 

 mal within the other (see fig. 3), when the several parts may 

 be submitted to a preliminary examination. It is found upon 

 the whole to be constructed in a very similar manner to that 

 described by the present author in Paralimnadia Stanley an a. 

 The dorsal ligament, however, by which the body is con- 

 nected to the shell above, occurs here at a rather consider- 

 able distance from the anterior extremity, whereas in the 

 Sydney species it is found close to the place where the 

 free anterior edges of the valves take their origin. For 

 this reason, the line of junction between the two valves in 

 the present form is not only visible behind the ligament, 

 but is continued in front of it to some extent, terminating 

 at the upper anterior angle. 



The anterior division of the body lying in front of the 

 dorsal ligament, is generally strongly deflcxed, though in the 

 living state of the animal it may have been allowed to 

 raise itself to some extent. The cervical segment is evenly 

 convex above, and defined from the head proper by a rather 

 deep depression, in the bottom of which a transverse suture 

 occurs joining the upper ends of the mandibles. The head 

 (see also PI. Ill, fig. 1) is about the length of the cervical 

 segment, and has the dorsal face strongly convex, carrying 

 somewhat in front of the middle a well-defined affixing 



