REPORT ON THE AMPHIPODA. 1343 



which attention is drawn in the diagnoses of the two families, there are also some notable 

 differences in the mouth-organs. The generic character — " peduncles of uropoda very 

 broad " — requires some modification, since the peduncles of the second pair are described 

 as narrow in Dairella California*,, Bovallius, and are narrow also in the species now to 

 be described. 



Dairella bovallii, n. sp. (PL CLVI1I.). 



Head wider than deep, deeper than long, not so long as the coalesced first and second 

 segments, together with the third segment of the perason ; each of the first three seg- 

 ments of the pleon longer than any of those of the peraeon, and having the postero- 

 lateral angles rounded ; the dorsal line of the specimen a little corrugated. 



Eyes occupying almost the whole surface of the head as seen from above or in profile ; 

 of the four groups of ocelli the lower pair are as large as the upper, which they almost 

 join at the sides of the head ; only the lower groups fold round to the front of the head, 

 where they are separated by a wide space. 



Upper Antennas standing wide apart on the upper part of the front of the head. In 

 the male, peduncle short, tumid, the first joint not longer than broad, the two 

 following very short, much broader than long ; the first joint of the flagellum broad, 

 narrowing a little apically, much longer than the peduncle, the tumid breast covered 

 with a large brush of elongate filaments ; the remainder of the flagellum comparatively 

 narrow, with small and slender filaments at intervals ; the second joint little longer than 

 broad, the third twice as long as the second, the fourth as long as the second and third 

 together, but thinner, the fifth a little shorter than the fourth ; the remainder broken. 

 In the female these antennae are slender, the first joint of the peduncle little dilated, 

 the flagellum consisting of a single long joint, slightly curved, of almost uniform breadth, 

 except at the apex which is not very acute. 



Loioer Antennas attached much below the upper ; the coalesced first and second joints 

 short, broader than long, the third joint smaller than these, the fourth smaller than the 

 third, the fifth longer than the preceding two together and forming an angle with them, 

 wider distally than at the base ; the first joint of the flagellum longer and abruptly much 

 narrower than the last of the peduncle, narrowing from the base to the middle, again a 

 little widened at the apex. Remainder of these antennas missing. In the female the 

 rudiments of these antennae, if present, were not observed. 



Upper Lip unsymmetrically bilobed by a narrow cleft in the distal margin, one lobe 

 being a little less deep than the other. 



Mandibles. — Cutting plate small, triangular, with straight, finely denticulate edge ; 

 there appears to be a similar secondary plate on the left mandible, but it was not clearly 

 made out ; the molar tubercle with broad multidenticulate crown, as usual straight-edged 



