3G4 PERCY SLADEN TRUST EXPEDITION 



11. Periclimenes (Cristiger) hrevinaris Nobili, 1905. 

 PericUmenes Borradailei, Nobili, Bull. Mus. Paris, 1905, iii. p. 159. 

 Periclimenes hrevinaris, Nobili, Bull. Sci. Tr. Belg. xl. p. 42, PL 3, fig. 7 (1906). 

 Persian Gulf. 



12. Periclimenes (Crtstiger) frater Borradaile, 1915 (Plate 53, fig. 6). 

 Ann. Mag. Nat. Hist. (8), xv. p. 210. 



Definition: Closely related to P. soror, but differing from it in that (1) the teeth on 

 the upper edge of the rostrum are closer set towards the tip than near the base, (2) there 

 are tivo distal spines on the first joint of the antennule, (3) the antennal scale decidedly 

 outreaches the first leg, (4) there is no accessory denticle on the dactylopodites of the 

 last three legs. 



Length of the longer of the two specimens, 13 mm. 



Seychelles, on reef 



13. Periclimenes (Cristiger) incertus Borradaile, 1915 (Plate 53, fig. 7). 

 Ann. Mag. Nat. Hist. (8), xv. p. 210. 



Definition: Closely related to P. parvus, but differing from it in that (1) the body 

 is more slender, (2) the rostrum is shallower, (3) there is a denticle on the carapace 

 behind the beginning of the rostral crest, (4) the third maxilliped is rather longer, owing 

 to the greater length of the penultimate joint, which is considerably longer than the 

 end joint. 



Length of the single specimen, 11 mm. 



Maldive Is. 



The specific distinctness of this form from P. parvus is somewhat doubtful. 



14. Periclimenes (Cristiger) commensalis Borradaile, 1915. 



Ann. 'Mag. Nat. Hist. (8), xv. p. 211. Potts, Pap. Dep. Mar. Biol. Carnegie Inst. 

 Washington, viii. p. 82 (1915). 



Definition : Body rather stout, not compressed ; rostrum reaching end of antennular 

 stalk, outreached by antennal scale, lanceolate, directed slightly downwards, its 

 formula -f ; supraorbital, hepatic, and antennal spines present ; cornea subhemispherical ; 

 first joint of antennular stalk broad, with moderate stylocerite and two distal spines, 

 second and third joints subequal, together shorter than first joint, flagella of a fair length, 

 the outer rather deeply cleft ; antenna with small basal spine, stalk nearly reaching 

 end of first joint of antennule, scale wide, with straight outer and convex inner side, 

 and distal spine of good size but not reaching end ; third maxilliped slender, reaching 

 end of antennal stalk, its long joint a good deal curved ; first leg reaching end of thicker 

 division of outer antennular flagellum, arm and wrist equal, hand shorter, fingers a little 

 longer than palm; second leg short, unarmed, its wrist subcorneal, hand nearly equal 

 to three preceding joints together, fingers equal to palm, not gaping, each with three 

 small teeth near base ; last three legs short, hairy, with a spine above and one below 

 end claw of short, rather stout dactylopodite ; telson shorter than uropods. 

 Torres Straits, on Comanthus annulatus. 



