308 



composed of only three joints. A very careful exami- 

 nation of the species has, however, shown that in all these 

 characters Van Beneden has fallen into some unaccount- 

 able error. The eyes under a strong lens are not faceted. 

 The seventh or last segment of the body is considerably 

 shorter than the sixth ; the first segment of the tail is 

 still shorter and abbreviated at the sides, whereas the 

 second, third, fourth, and fifth segments are of equal size, 

 perfectly distinct in their articulations, and with the 

 posterior-lateral angles of each produced into an acute 

 point like the terminal segments of the body ; the sixth 

 or terminal segment of the tail is of large size, semi- 

 ovate, and has a deep transverse impression near the base 

 (this impression is not represented in our outline figure, 

 but it seems to correspond with Van Beneden's narrow 

 penultimate segment). 



The upper antennas are very short and cylindrical, 

 composed of three basal joints, arising from a fixed base, 

 the third being as long as the two preceding joints taken 

 together, followed by three small articuli, of which the 

 last is very minute, and almost concealed by terminal 

 setse. The lower antennas are about two-thirds of the 

 length of the animal, having five basal joints, thicker 

 than the remainder, extending to the extremity of the 

 upper antennas, followed by a long very slender flagel- 

 lum, composed of a great number of minute articuli. 

 The mandibles are horny, with several conical teeth at 

 the tip, and with a slender movable blade attached to 

 the inner margin, having a finely serrated upper edge. 

 They externally bear a slender three-jointed palpiform 

 appendage. 



The foot-ja\vs are six-jointed, the joints of moderate 

 width, the second having the inner apical angles pro- 

 duced, the remainder being armed with bristles on the 



