REPORT ON THE AMPHIPODA. 1417 



Euthemisto australis, n. sp. 



Back very slightly or not compressed ; first three segments of the pleon large, witli 

 the postero-lateral angles produced into acute points and the lower margins serrulate. 



Upper Antenna!. — First joint of the peduncle nearly as broad as long, the two 

 following joints short ; first joint of the flagellum broad and long, fringed with a brush 

 of filaments, the second and third joints very short, followed by eight slender joints. 



Lower Antenna;. — Gland-cone conspicuous, the three free joints of the peduncle as in 

 the other species ; the flagellum (in the male) of many long and slender joints, together 

 sometimes nearly as long as the animal. 



Mouth-Organs so far as observed similar to those in the other species, but in the 

 mandibular palp the second joint is about twice as long as the first and a very little 

 longer than the third. 



The G-noihojyods agree closely with those of small specimens of Euthemisto gaudi- 

 chaudii (see PI. CLXXIIL). 



First Perseopods. — The first joint narrow at the neck, which is a little bent, widened 

 below, with two little spines on the lower part of the hind margin ; the front margin 

 channelled below ; the second joint with two spines on the hind margin ; the third joint 

 widening distally, longer than the second joint, the hind margin nearly straight, very 

 hairy, carrying three Little spines ; the fourth joint longer than the third, widening 

 distally, the hind margin continuous with that of the preceding joint, and hairy like that, 

 carrying four spines, not so long as the front margin which is smooth and a little convex, 

 the inner surface having a row of five unequal spines, the distal margin sinuous, pro- 

 jecting behind the fifth joint, on the inner surface minutely pectinate ; the fifth joint 

 longer but much narrower than the fourth, the front margin convex, smooth except for a 

 few Httle spinules, the hind margin straight, pectinate, and carrying six or seven spinules, 

 the inner surface armed with eight unequal spines ; the finger curved, smooth, scarcely 

 half the length of the fifth joint. 



Second Perseopods similar to the first, except in the first joint which is longer, and 

 the fourth which is longer and scarcely so broad, forming a narrow oval, without the 

 characteristic distal widening found in the preceding pair, so that below the lowest spine 

 of the hind margin there is here a further tract of that margin, which in the preceding 

 pair is bent so as to form part of the distal margin ; the fifth joint not longer than the 

 fourth, and not longer than the corresponding joint in the first perseopods. 



Third Perseopods. — First joint narrow above, widened below, channelled behind, 

 with the outer margin triflingly serrate, the sinuous front margin having some small 

 spines ; the second joint short ; the third more than twice as long as the second, the 

 straight front margin hairy, carrying some spinules, and at the apex a spine, and a 

 smaller one within the apex, the hind margin produced into a subacute apex carrying a 



(ZOOL. CHALL. EXP. PART LXVIJ. 1888.) Xxx 178 



