THE GENUS LEBERTIA. 503 



body, and the latter by the epimeral plate, which is similar in 

 size to the dorsal plate. The skin of the lateral surface between 

 the edges of the plates is soft and marked by tine lines running 

 the length of the body. Along this area dorsally there are nine 

 pairs of long stiff bristles in two rows, an inner of four pairs and 

 an outer or more lateral one of five pairs. The dorsal plate has 

 three pairs two pairs lying close -3 front of the eyes and a 

 small pair representing the antenniform bristles. The ventral 

 surface also has a few hairs two pairs on or near the edge 

 of the epimeral plate posteriorly being pectinate. Quite a 

 number of these hairs may extend beyond the margin of the 

 body. 



The capitulum is about - 0S mm. long. It extends well beyond 

 the bay formed by the first pair of epimera, and curves well 

 towards the ventral surface. About midway up each side the 

 palpi are articulated. The third and fourth segments are pro- 

 minent by reason of their stoutness. The third segment has one 

 strong bristle on its outer side, while the fourth has a moderately 

 long curved claw. The fifth segment is of a rudimentary type : 

 it lies somewhat recessed into the fourth segment, and has two 

 long and three short hairs springing from it. 



The larva possesses only three pairs of legs, which are grouped 

 well, towards the anterior end of the body. The first pair may 

 measure up to 0*20 mm., the second pair 027 mm., and the third 

 pair 0*30 mm. Swimming hairs are entirely wanting, but loco- 

 motion is aided by a varying number of moderately long, simple 

 or weakly pectinate straight bristles, which are to be found in 

 greatest abundance on the third pair of legs. Each leg ends 

 in three fine, long, curving claws, of which the middle one is the 

 smallest. 



Corresponding to the number of pairs of legs, there are only 

 three pairs of epimera. The suture dividing those of one side 

 from the other is well marked, as well as that dividing the first 

 pair from the second. Only a very short rudimentary lateral 

 suture separates the second pair of epimera from the third. The 

 posterior portion of the third pair is cut away obliquely on the 

 median line ; within this recess there is a small weakly chitinised 

 post-epimeral plate, which Piersig called the anal plate, but 

 which Thor prefers to consider as the rudiment of the provisional 

 genital area found in the nymph. 



