/ o 



Glyptometra 



may bear a low, blunt or- sharp, carinate ridge which, however, 

 is never elevatecl into au overlapping spine or tubercle 

 f 1 a low sharp median keel of uniform height on the ossicles 

 of the division series and all, or nearlv all, of the brachials; 

 ossicles of the division series and earlier brachials with 

 abruptly everted borders and more or less numerous small 

 tubercles or capitate spines scattered over the dorsal surface; 

 10 — iS (usually 10 — 12) arms 100 mm. to 140 mm. long; 

 IIBr 2 or 4(3 + 4); cirri XV — XX, 13 — 15 (Philippine 



Islands; 92 — 761 Metres) 



f 3 dorsal surface of the ossicles of the division series and 

 brachials evenly rounded, or with a blunt median carination, 

 or a broad low median tubercle, never with a low sharp 

 median keel ; proximal and distal borders of the ossicles of 

 the division series and of the lower brachials never everted 

 and standing up at right angles to the general surface of 

 the segments; no definite isolated small tubercles or capitate 

 spines on the dorsal surface of the ossicles of the division 

 series or earlier brachials, which are dorsally evenly rounded, 

 irregularly rugose, or bluntly carinate 



g 1 centrodorsal more or less conical, with the cirrus sockets 

 arranged in ten definite columns, two in each radial area 

 h 1 26 — 3 3 arms; IIBr series always 4 (3 + 4) (Kei Islands 

 to the Malay Archipelago, the Philippine Is- 

 lands and southern Japan; 54 — 403 Metres) Crossometra 

 Ir not more than 20 (usually 10 — 20) arms; IIBr series, 

 when present, usually 4 (3 + 4), sometimes 2 (Lac- 

 cadive Islands to Timor and the Kei Is- 

 lands, and northward to the Philippines 

 and southern Japan; j $ — 1269 Metres) 

 g" centrodorsal thick discoidal or more or less columnar, 

 the cirrus sockets arranged in 1 5 crowded columns 

 h 1 12 — 28 arms 



i 1 all division series 2 ; extremely brittle and easily 

 broken at the synarthries; 15 — 19 arms; cirri 

 XXX, 19 (Moluccas and Philippine Islands; 



Perissometra 



118 — 243 Metres) 



Monachometra 



i 3 IIBr series 4 (3 + 4); tough, the arms, rarely broken 

 at the base during capture ; 14 — 28 arms; cirri 

 XX — XXX, 15 — 24 (South Africa to the Phi- 

 lippine Islands and Fiji; 360 — 13 14 Metres) 



Pachylometra 



