REPORT ON THE AMPHIPODA. 1379 



1887. Lestrigonus, Giles, On Six New Amphipods from the Bay of Bengal, Journ. Asiat. Soc. 



Bengal, vol. lvi. No. 2, p. 224. 

 1887. Hyperia, Hansen, Malacostraca marina Groenlandia? occidentalis, p. 56. 

 188S. „ Robertson, Catal. Aniph. and Isop. of Clyde, p. 64. 



For the original definition of the genus see Note on Desmarest, 1825 (p. 122). For 

 the definition of Hiella, see Note on Straus-Durckheim, 1829 (p. 139); for that of 

 Lestrigonus, see Note on Milne-Edwards, 1830 (p. 142). Bovallius in 1887 defines 

 Hyperia as follows :- 



" Head large, nearly globular, flattened anteriorly. Pereion smooth, in the females 

 larger and more tumid than in the males. Carpus of first pair of pereiopoda [wrist of 

 First Gnathopods] dilated, less produced than in second pair, the produced carpal process 

 in both pairs spoon-shaped. Carpi of third and fourth pair [fourth joint of the First and 

 Second Perae-opods~] not dilated. Last three pairs subequal, not or only a little longer 

 than the two preceding pairs. Epimerals distinct. Uropoda short and broad. Telson 

 very large." 



Hyperia sibaginis, n. sp. (PI. CLXV.). 



First and seventh segments of the perseon dorsally the longest ; the first three 

 segments of the pleon much longer than any of the perseon-segrnents, the postero-lateral 

 angles almost right angles, the produced points being minute in the first and second 

 segments, and the third having none. 



Upper Antennas. — The peduncle short, the first joint tumid, not longer than broad, the 

 two following joints very short ; the first joint of the flagellum somewhat bent upwards, 

 narrower than the peduncle, but longer, its lower margin longer than the upper, clothed 

 with a brush of filaments, of which the longest are near the base ; the remainder of the 

 flagellum is linear, fringed with setules, of twenty-three joints, of which the first and 

 second are the shortest, rather stouter than the rest. 



Lower Antennae. — The third (first free) joint of the peduncle not longer than broad, 

 second rather shorter, third longer, bent a little upward, the proximal part wider than 

 the distal ; the flagellum linear, much longer than that of the upper antennae, fringed in 

 a similar manner, of about thirty joints, which are rather longer than those of the upper 

 antennas, the first not short, bulbous at its base. 



Upper Lip unequally bilobed, the apical cleft rather deep. 



Mandibles almost rectangular, with the palp fixed at the upper front angle, the 

 small cutting plate projecting at the angle below, while the lower angle to the rear is 

 rounded; the cutting edge divided into nine denticles, the rather narrower secondary 

 plate of the left mandible having an edge of ten or a dozen denticles ; behind these plates 

 is a group of spinules on the lower margin, immediately to the rear of which projects the 



