204 PERCY SLADEN TRUST EXPEDITION 



Portunidse. 



28. Parathranites orientalis Miers. 

 Parathranites orientalis Alcock (4), p. 17. 



Salomon Bank, 60—120 fms. ; 1 ?. C. 1. 13 mm., C. b. 187 mm. 



29. Caphyra rotundifrons (A. Milne Edwards). 



Caphyra rotundifrons Rathbun, Mem. Mus. Comp. Zool., xxxv. 1907, p. 60, pi. 1, 

 fig. 4. 



Praslin, reef; 1 $ ovig. 



30. Caphyra hemisphcerica, sp. nov. (Plate 15, fig. 9). 

 Coetivy, 32 feet, by diver ; 1 £. 



C. 1. 3'5 mm., C. b. 3*7 mm., thickness 2 mm. 



Carapace hemispherical, smooth to the naked eye, microscopically granulous on 

 anterior third ; 2 fine transverse ridges, one at the middle running across the carapace, 

 with two interruptions, and curving forward, to the last lateral tooth ; the other further 

 forward on the gastric region. Front truncate, a minute median notch, and indications 

 of a shallow lobe on each side of it ; outer angles rounded off and separated by a large 

 triangular notch from the subacute but less advanced preorbital angle. Four small antero- 

 lateral teeth, including the post-orbital angle, and diminishing in size from first to fourth. 



One cheliped and 2 legs only are present ; inner, lower margin of ischium and 

 proximal half of merus armed with slender spines ; hand with a blunt superior marginal 

 line ; the dactyli of the legs are strongly curved and taper rapidly to a long, slender spine 

 which occupies nearly half their length. 



Allied to C. Icevis A. Milne Edwards (Nouv. Arch. Mus. Hist. Nat., ix. 1873, p. 173, 

 pi. 4, fig. 2) and to C. natatrix Zehntner (Rev. Suisse Zool., ii. 1894, p. 162, pi. 7, 

 fig. 10) but differs in the greater convexity, in the front being less cut up into teeth, in 

 the fewer and smaller antero-lateral teeth, in the unarmed wrist and palm. 



31. Lissocarcinus polybioides Adams and White. 

 Lissocarcinus polybioides Alcock (4), p. 19. 

 Seychelles, 31 fms., Sta. F 2; 1 small $. 



32. Lissocarcinus orbicularis Dana. 



Lissocarcinus orbicularis Alcock (4), p. 20. 



Salomon; 1 $, 1 $ ovig. Cargados Carajos, 30 fms., Sta. B 23; 1 ?. Saya de Malha, 

 55 fms., Sta. C 15 ; 1 ?. 



33. Portunus (Achelous) petreus (Alcock). 



Neptunus (Amphitrite) petreus Alcock (4), p. 37 ; Illus. Zool. Investigator, Crust., 

 pt. viii, 1900, pi. 46, fig. 2. 



Cargados Carajos, 30 fms., Sta. B 3; 1 $ : 30 fms., Sta. B 17; 1 ?. Providence, 

 39 fms., Sta. D 1 ; 1 $. 



$, Sta. D 1, C. 1. 17'6 mm., C. b. (inch spines) 27 "3 mm. 



