S. I. Smith on Brazilian Crustacea. 29 



thickly ciliated. The three anterior segments of the peduncle are 

 cylindrical, and the last (carpal) is much longer than in most species 

 of JPeneus, so that it reaches to the middle of the antennal scale. 

 The flagellum is very much longer than the Avhole length of the body. 



The second pair of maxillipeds, when extended, reach nearly to the 

 base of the antennal scale ; the merus is nearly three times as long as 

 broad, and thickly hairy on the inner edge ; the exognatli is very 

 slender, clothed along the edges with long cilia, and scarcely reaches 

 the tip of the extended dactylus. The external maxillipeds reach 

 slightly beyond the middle of the antennal scale and are thickly 

 setose along the inner edges ; the exognath is slender, extends slightly 

 beyond the merus of the endognath, and is ciliated as in the maxilli- 

 peds of the second pair. 



The thoracic legs of the first pair reach about to the middle of the 

 propodus of the external maxillipeds, are slender and beset with stiff 

 hairs along the edges, and the basis is armed with a short spine on 

 the inner side near the articulation with the ischium. The second and 

 third pairs of legs are successively a little longer, perfectly smooth, 

 and the basal segments unarmed. The legs of the fourth and fifth 

 pairs are smooth and unarmed, and all the segments, except the coxal 

 and basal, are very slender and very much prolonged, the terminal 

 segments being fully as slender as the terminal portions of the flagella 

 of the antennulae. 



The abdomen is compressed, and upon the fourth, fifth and sixth 

 segments there is a dorsal carina which is high and sharp upon the 

 sixth, and terminates posteriorly in a slight tooth upon the fifth and 

 sixth. The terminal portion of the appendages of the first segment 

 is long, slender and ciliated along the edges ; in the appendages of 

 the four succeeding segments the outer of the terminal branches are 

 like the tenninal portion of the appendages of the first segment, and 

 of about the same length, while the inner branches are but half as 

 long. The penultimate segment is strongly compressed, and its lamel- 

 liform appendages are rather long and naiTOw, the inner ones project- 

 ing considerably beyond the terminal segment, ciliated alono- both 

 edges and narrowly triangular at tip, the outer ones ciliated along 

 the inner edges and rounded at the tip. The terminal segment tapers 

 regularly to a very slender and acute point, the edges of the terminal 

 half are ciliated, and there is a deep median groove upon the dorsal 

 surface. 



In the male, the appendages of the first abdominal segment (plate 

 I, fig. 1=^), are connected together near their bases by a peculiar sexual 



