92 BULLETIN OF THE 



The eyes are large, reniforra, and black, as in the typical species of 

 Penctus. 



The peduncle of the anteniiula is much longer than the rostrum ; the first 

 segment is more than half the entire length, excavated above for the reception 

 of the eye, but the lamelliforni appendage is small, narrow, and concealed 

 between the eyestalks ; the second segment is about half as long as the first, 

 and somewhat triquetral ; the body of the ultimate segment is not quite half 

 as long as the second, but is prolonged in a narrow process beneath the bases 

 of the flagella ; the upper flagellnm is slender, cylindrical and longer than tlie 

 carapax and rostrum ; the proximal portion of the lower flagellum is slender 

 and cylindrical, like the upper, but the terminal portion is wanting in all the 

 specimens seen. 



The antennal scale is about half as long as the carapax including the rostrum, 

 nearly four times as long as broad, and contracted distally to a rather narrow 

 but evenly rounded tip, which projects scarcely beyond the terminal spine of 

 the outer margin. The second segment of the peduncle of the antenna is armed 

 with a slender spine just outside the articulation of the scale, and the con- 

 solidated fourth and fifth segments reach nearly to the middle of the scale and 

 are subcylindrical. The flagellum is slender, cylindrical, and three or more 

 times as long as the rest of the animal. 



The labrum, metastome, and crowns of the mandibles are nearly as itt 

 Penaeus. The mandibular palpi (PI. XVI. fig. 1) are very much as in the 

 Amalopenceus just described, and reach to about the middle of the antennal 

 scales: the proximal segment is about half as broad as long and once and two 

 thirds as long as the distal segment, which is three times as long as broad, and 

 ovate with the tip obtuse. 



The proximal lobe of the first maxilla (PI. XVI. fig. 2) is large, broadly 

 rounded at the extremity, and armed with very long setiform spines and setse ; 

 the distal lobe is broad and truncated at the extremity, and armed with slender 

 spines and setse rather shorter than on the proximal lobe ; the endognath is 

 shorter than the distal lobe of the protognath, has a slight expansion margined 

 with hairs on the outer edge near the base, and tapers to an obtuse tip (Fig. 2") 

 armed on the inner edge v-'itb three very long and distally plumose setae, and 

 on the anterior surface with very delicate hairs. 



The second maxilla (PI. XVI. fig. 3) is very much as in many species of 

 Pcnrcus. The three proximal lobes of the protognath are subeqnal and narrow, 

 and the distal lobe about twice as wide as they, but still rather narrow and ovate. 

 The endognath is much shorter than the distal lobe of the protognath, and termi- 

 nates in a narrow thickened fold (Fig. 3*) on the posterior side armed along either 

 e(lge and on the anterior side with a longitudinal series of slender spines or 

 spiniform setae, of which the distal one on the inner edge, the anterior series, 

 and the distal ones of the onter series are very long. The anterior lobe of the 

 scaphognath is long and very narrow, and projects considerably beyond the 

 protognath, while the posterior lob^e is large, broad, and curved strongly inward 

 and anteriorly as in the allied genera. 



