BORRADAILE— ON THE PONTONIIN^ 387 



Genus PoNTONiDES n. gen. 



Definition : Body stout, depressed ; sixth abdominal segment not elongate ; rostrum 

 short, flat horizontally, subtriangular, curved downwards, not dentate, with slight keels 

 above and below ; eye well developed ; outer flagellum of antennule not deeply cleft ; 

 antennal scale broad ; mandible without palp ; maxillipeds without exopodites, second 

 maxilliped without podobranch, with last joint mediad of preceding joint ; third 

 maxilliped with vestigial arthrobranch and with all joints broad ; legs moderately stout, 

 last three ending in simple, nearly straight dactylopodites without basal prominence. 



Type: Pontonides maldivensis (Borradaile), 1915 (Plate 57, hg. 28). 



Pontonia maldivensis, Borradaile, Ann. Mag. Nat. Hist. (8), xv. p. 213 (1915). 



Definition : Body much depressed ; carapace broader than long, with small spine 

 behind antenna and a blunt process below it ; rostrum not reaching end of first joint of 

 antennule, sharp pointed both in horizontal and in vertical view ; first joint of antennular 

 stalk broad, its spines sharp but not very long, third joint a little longer than second, 

 flagella of a fair length ; antennal scale ovate, longer than antennular stalk, its distal 

 spine very small ; last two joints of third maxilliped but little twisted from horizontal 

 plane ; first leg outreaching antennular stalk by hand and part of wrist, hand and wrist 

 subequal, each rather shoi-ter than arm, fingers equal to palm ; second legs unequal, the 

 larger about twice as long as carapace but shorter than body, its hand long, parallel- 

 sided, with short, simple fingers, smaller hand with short swollen palm and long, slender, 

 simple fingers ; last three legs with long, slender dactylopodites ; telson shorter than 

 uropods. 



Length of longest specimen, 7 mm. 



FadiflFolu Atoll, Maldive Is. 



Genus Anchistus Borradaile, 1898. 



Ann. Mag. Nat. Hist. (7), ii. p. 387. Nobili, Bull. Sci. Fr. Belg. xl. p. 48 (1906). 

 Tridacnocaris, Nobili, Ann. Mus. Geneva, xl. p. 235 (1899). 

 Marygrande, Pesta, Zool. Anz. xxxviii, p. 571 (1911). 



Definition : Body stout, usually swollen and somewhat depressed ; sixth abdominal 

 segment not elongate ; rostrum of fair length, compressed, bent or curved downwards, 

 with broad, usually rounded end, dentate at the tip only or without teeth ; outer 

 flagellum of antennule not deeply cleft ; antennal scale broad ; mandible without palp ; 

 inner lacinia of maxillule broad and hairy; second maxilliped without podobranch, with 

 last joint mediad of preceding joint ; third maxilhped with vestigial arthrobranch, and 

 with last two joints narrow, together longer than preceding joint, which is broad or 

 narrow ; legs stout, directed outwards, the last three with curved dactylopodites, with 

 or without a small tooth on the lower side, without basal protuberance. 



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