G. M. Thomson. — On new Crustaceans. 235 



Fam. IDOTEIDJE. 

 Genus Edotia, Guerin-Meneville. 



1. Edotia dilatata, n. sp. PI. xii., figs. 9, 10. 



Female. — Body somewhat flattened and much dilated in the middle, the 

 second, third and fourth segments heing progressively hroader and bluntly 

 angled at the sides, fifth suddenly narrowing to less than half the width of 

 the fourth ; epimera completely amalgamated with the thoracic segments. 

 Post-abdomen 2-jointed, the 1st joint very short, 2nd greatly elongated ; 

 distal extremity somewhat excavate. 



Head subquadrate, with the anterior margin nearly straight, posterior 

 slightly rounded. Antennules (internal antennae) very short, 4-jointed, 

 basal joint stout. Antenna? (external antennas) reaching to the second 

 thoracic segment, flagellum 13-14-jointed. Legs slender, subequal, dactyla 

 of all the feet double-clawed (terminal and sub-terminal claws subequal). 

 Opercular plates elongated, narrow ; distal portions sub-quadrate, their 

 extremities terminating in a point on the inner line, rounded outwardly. 

 The whole body is of a light chestnut-brown colour, and the surface is quite 

 smooth ; the abdomen bears numerous minute black dots. Length about 

 1 inch. The whole under-surface was occupied by an ovigerous pouch. 



This is a remarkable species intermediate in many respects between 

 Edotia and Idotea, though apparently on the whole nearest to the former. 

 It differs however from the characters of the genus in which I have placed 

 it, in wanting the characteristic oblique line across the basal opercular 

 plates. From Idotea it differs most conspicuously in having the epimeras 

 anchylosed with the sides of the thoracic segments. The ova in the oviger- 

 ous pouch were not sufficiently developed to furnish auy characters. 



A single specimen was sent to me from Auckland by T. F. Cheese- 

 man, Esq. 



Fam. OBCHEST1TM3. 

 Genus Allorchestes. 



Allorchestes recens, n. sp. PL xiii., figs. 2-5. 



Body tolerably compressed and slender, quite smooth ; coxal plates of 

 the first three thoracic segments about as deep as their respective segments ; 

 those of the rest of pereion shallower. Eyes rather small, nearly circular. 

 Superior antennas reaching to or slightly beyond the extremity of the 

 peduncle of the inferior ; peduncle about as long as the 5-7 -join ted 

 flagellum. Inferior antennas about one-fourth as long as the body ; 

 peduncle about equal with the 8-10-jointed flagellum. In both antennas 

 a few very short stiff setas are found at the extremity of each joint. The 

 maxillipedes have an extremely short and pointed dactylos ; most of the 

 joints have numerous short stiff setas at their extremities and inner 



