682 Allorchestes 



Body compressed, especially at pleon. Side-plates 1 — 4 deep, 4*^ also 

 Wide, 5**^ shallow, 2^—4*^ quadrate. Pleon segment 3, postero-lateral corners 

 quadrate, with miuutely produced point. Eyes oval, wider apart than the longer 

 diameter. Antennael and 2 ofrather variable proportions (in yoiing fromm other's 

 pouch subequal). Antenna 1 usually rather longer tban peduncle of antenna 2, 

 flagellura 10— 20-jointed. Antenna 2, flagellum shorter or not much longer than 

 peduncle, 10— 20-jointed, upper lip broader than deep. Maxilla 1, palp 

 minute. Maxillipeds, 2"^ and 3*^ joints of palp broad. Gnathopod 1 in (5^, 

 5*^ Joint slightly longer than 6*^ widest subapically, with spinules at the 

 projection of front and bind margins, 6*^ Joint oblong, a little widened at 

 almost transverse convex palm, front margin convex, bind rather sinuous, 

 finger fitting palm. Gnathopod 2 in (5 robust. 2^ Joint with small downward 

 produced lobe, 3*^ also with front margin lobed, 4*^^ apically produced behind, 

 5*^ produced backward in a rather slender and not strongly spiued läppet, 

 6*^ large, the palm spinulose, very oblique, defined from the slightly bulging 

 bind margin by palmar spines and the small hollow which receives the apex 

 of the strong finger. Gnathopod 1 in Q as in d, except that 6^^ Joint is 

 more elongate, as long as 6^^. Gnathopod 2 in 9 rather larger than 

 gnathopod 1, 2*^ Joint not produced downward, 3*^ without conspicuous lobe, 

 4**^ produced as in ö, b^^ with läppet stretching along part of straight bind 

 margin of 6*^ G^^^ broader than iu gnathopod 1, slightly widening to the 

 transverse palm, finger matching palm. Branchial vesicles large, oval, with 

 narrow neck. Marsupial plates broad, oblong, produced at one coruer, setae 

 Short. Peraeopods 1 and 2 subequal, slender. Peraeopod 3, 2^ Joint oblong 

 oval, front margin with spines, nearly straight, bind margin nearly smooth, 

 A^^ Joint widened, spinöse on both margins. Peraeopod 4 considerably longer, 

 2^ and 4*^ joints not quite so wide; branchial vesicles in peraeopods 3 and 4 

 with accessory lobe. Peraeopod 5 shorter than peraeopod 4, especially in d, 

 but 2^ Joint much larger and more rounded behind. widest subapically and 

 broadly produced behind 3*^ Joint, 4*'^ not much widened, finger as in all 

 the peraeopods short, curved. üropod 1, rami decidedly shorter than peduncle. 

 üropod 2, rami a little shorter than peduncle. üropod 3, ramus small, 

 conical, shorter than stout peduncle, tipped with a minute spinule. Telson 

 broad, the 2 quadrate lobes, separated by a linear fissure, set at an angle 

 to one another, gable-like. Surface ornamented with coloured spots and 

 white dots (Haswell). L. 11 — 20 mm. 



Southern Indian Ocean and South-Pacific (south- and west-coasts of Australia, 

 Tasmania). 



3. A. malleolus Stebb. 1899 A. m.. T. Stebbing in: Tr. Linn. Soc. London, 

 ser. 2 V.7 p. 409 t. 33A. 



Body moderately compressed. Side-plates 1 — 4 rather deep, with no 

 projecting point of bind margin. Pleon segment 3, postero-lateral corners 

 bluntly produced. Eyes not large, rounded, at least their diameter apart, 

 dark in spirit. Antenna 1 about ^^ as long as antenna 2, joints of peduncle 

 successively shorter, flagellum longer than peduncle, 10 — 12-jointed. An- 

 tenna 2 not more than % as long as body, peduncle stout, flagellum shorter 

 than peduncle. 10 — 12-jointed. In young from the marsupium antenna 1 

 not shorter than antenna 2, flagellum of each 2- or 3-jointed. Maxilla 1, 

 palp minute, on well defined Interruption of bind margin of outer plate. 

 Maxilla 2, principal seta on inner margin of inner plate not very elongate. 

 Gnathopod 1 in d, 2^ Joint widening rapidly to the middle, 4*^ not longer 

 than 3^, 5*^ little longer than 6*^, widest subapically, with spines on both 



