AMPELISCA GAIMARDII. 129 



and below, two or three very minute hairs ; the second 

 articulus likewise carries a single auditory cilium. The 

 inferior antennae are as long again as the superior, and 

 reach to about two-thirds of the length of the animal. 

 The third and fourth joints of the peduncle are furnished 

 on the upper margin with fasciculi of hairs, the former 

 through the entire length, the latter for a portion only ; 

 the last joint of the peduncle is longer and more slen- 

 der than the preceding one : the tiagellum, of which 

 the first articulus is longer than either of the others, is 

 very long and very slender, and is furnished with a few 

 very minute cilia. The mandibles have the incisive 

 margin armed with four or five strong teeth ; within is 

 a second plate, articulated with the mandible, and equally 

 strongly armed ; deeper within exists a broad strongly 

 toothed molar process, between which and the moveable 

 plate already referred to stands a row of stiff forked 

 spines, each of which is denticulated along the margins 

 throughout its length : the appendage of the mandibles 

 has the first joint very short, not being longer than 

 broad ; the second is very broad, and forms a long 

 ellipse, having the upper margin furnished with four fas- 

 ciculi of hairs ; the third joint is scarcely as long as the 

 second, very much more slender, slightly curved, and 

 of equal breadth throughout ; the underside is fur- 

 nished with a few hairs, commencing near the middle, 

 and increasing in length towards the apex. The foot- 

 jaws have the finger long and slender ; the sixth joint, or 

 hand, is short ; the wrist is longer than the hand and 

 finger together, but the joint anterior to the wrist is 

 very short, and carries a large squamiform plate, arcuate 

 upon the outer, and straight upon the inner side, armed 

 with six slightly-curved simple teeth, the most anterior 



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