REPORT ON THE AMPHIPODA. 1497 



tumid, bent so that the convex lower margin with the brush of slender filaments is 

 much longer than the upper, which has at its apex two broad filaments ; the second joint 

 not broader than long, not so broad as the narrowed apex of the first joint, carrying 

 three filaments ; the third joint narrower but much longer than the second, with two 

 filaments near and one at the apex ; the fourth joint missing. 



Tn the female, first joint cylindrical, bent, much longer than broad, second joint about 

 half as long as the first, third half as long as the second and narrower, not longer than 

 broad, with some apical setules ; first joint of the flagellum longer than the last of the 

 peduncle, carrying some filaments, second joint longer and more slender than the first, 

 third more slender than the second. 



Lower Antennae inserted at the lower part of the back of the head. In the male, the 

 second joint of the peduncle (perhaps including the first in coalescence) is distinct, 

 broader than long ; the next or third joint is much longer, but tolerably stout, narrowing 

 distally, smooth-edged, more than a quarter but less than a third the length of the 

 following joint, which is slender, ciliated, distally bulging ; the fifth joint is similar to 

 the fourth, but more slender and a little longer; the first joint of the flagellum is not 

 quite two-thirds the length of the last of the. peduncle, much more slender ; the 

 second joint is not quite two-thirds of the first in length. 



In the female, the third (first free) joint of the peduncle slender, scarcely longer than 

 the fourth, the fourth with a subapical setule, the fifth a little longer than the third, with 

 a setule remote from the apex ; the first joint of the flagellum in line with the peduncle, 

 rather narrower and shorter than the preceding joint, with three setules near the apex ; 

 second joint much narrower and shorter than the first, with a group of very small apical 

 setules. 



Mouth Organs very small, and from the delicacy of their texture difficult to 

 manipulate in dissection. The Epistome forms a shallow dome over the cutting edges of 

 the mandibles ; the Mandibles are long and narrow, the trunk rather deeper near the 

 base than further on, the cutting edge and secondary plate of the left mandible 

 apparently represented by two bent teeth, the palp attached near the base of the 

 trunk, which it exceeds in length, the first joint longer than the second, the third 

 longer than the first, narrow, tapering to a fine point ; the First Maxillse are long, 

 narrow, extremely transparent plates, the outdrawn triangular termination having on 

 the inner margin close to the apex four minute teeth ; the shape of the Second Maxilla} 

 was not discovered ; the outer plates of the Maxillipeds are broad, overlapping, with 

 convex outer margin. 



First Gnathopods. — The side-plates deeper than broad, the front margin convex, 

 the lower margin with two setules near the rounded front angle. The first joint attached 

 near the middle of the hind margin of the side-plate, slightly bent, nowhere broad, but 

 broader below than above ; the second joint scarcely longer than broad, having like the 



(ZOOL. CHALL. EXP. — PAET I.XVII. 1888.) Xxx 188 



