370 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxm. 



Median area with a transverse groove a little in front of its center; the 

 three eyes close together and arranged in the form of a triangle, two 

 in front of this groove and one behind it. Transverse grooves divid- 

 ing the lateral areas placed far back, only a little in front of the poste- 

 rior margin of the carapace and curved forward. Frontal plates 

 narrow and showing but little in dorsal view. 



Free segments short and telescoped together so that the posterior 

 lobes of the carapace touch or overlap the third pair of dorsal plates. 

 First dorsal plates lateral and nearly concealed beneath the carapace 

 and its posterior lobes; but they extend forward under the carapace 

 and each bears an adhesion pad on its anterior margin as in Pandarus. 

 Second dorsal plates median and rudimentary, like those just starting 

 in young females of Pandarus and Perissopus. Third dorsal plates 

 enormous, as wide as the carapace, and covering two-thirds of the 

 genital segment. Each is armed at its anterior corner with a short 

 but stout spine ; the plates do not quite meet at the mid-line and are 

 armed along their entire median and posterior borders with sharp 

 spines, thickly set. Genital segment elliptical, one-third narrower 

 than the carapace, with wide and conical posterior lobes. From the 

 tips of these lobes extend the modified fifth legs in the form of narrow 

 pointed processes whose bases reach forward on the ventral surface to 

 the base of the abdomen. Although every species thus far examined 

 shows these fifth legs on the ventral surface, the present species and 

 neozealanicus are the only ones in which they extend beyond the tips 

 of the posterior lobes so as to become visible in dorsal view. The 

 rudimentary sixth segment lobe is about half the width and length of 

 the posterior lobes of the genital segment, and is evenly rounded. 

 It is on a level with the dorsal surface of the carapace and is entirely 

 visible from above. 



Abdomen wedge-shaped, relatively large, but placed so far forward 

 on the ventral surface of the genital segment that only the anal laminse 

 are visible from above. These lamina? are twice as long as wide and 

 are each tipped with two or three rudimentary setae, short and non- 

 plumose. 



First antennae of the usual pattern, terminal joint slender and club- 

 shaped. Second antennae stout and placed far back of the anterior 

 margin, opposite the base of the mouth-tube; terminal claw short, 

 strong, and well curved. First adhesion pads obovate, of medium 

 size, and close to the lateral margin; second pair very small and nearly 

 circular; third pair ellipticaland larger than the second; fourth pair 

 on the outer margins of the first dorsal plates as in Pandarus, elliptical 

 and the same size as the third pair. In addition to these four pairs 

 there are also adhesion pads on the basal joints of the first and third 

 pairs of swimming legs. One pair on the first legs close together on 



