MARINE CRUSTACEANS. 243 



being true coral crabs, are often found in coral stocks, and in the Actaeas of the flosculata- 

 gi'oup, of whose habits as yet nothing is kno\vn, since they have only been taken with the 

 dredge. Actaea speciosa (Fig. 42 O) is an example of a species in which the flange is not 

 found. The object of the apparatus is, no doubt, to enable the end-joint to be moved more 

 evenly and accurately and held fast in any position ; and it is only an elaboration of structures 

 found in most crabs, which have usually a small facet on the hinder side of the last joint for 

 the end of the propodite. Its absence is, nevertheless, particularly interesting in the case of 

 Eriphia, which is allied to Doniecia, and of Pseudozius other than the two species mentioned 

 above. A single glance at the orbits of these latter species is enough to show that they have 

 no place among the Trapeziinae, Eriphiinae, or Etisinae, so that the formation of the legs in 

 question must have arisen, like so many other chai-acters of the crabs, independently in two 

 or more cases^ It is probably an adaptation to clambering. 



4. Pseudozius triunguiculatus, n. sp. (Fig. 44). 



Diagnosis : " A Pseudozius with the carapace flat, smooth (microscopically roughened) and 

 hairless, the regions not marked out ; the front sloping slightly downwards, standing well forward 

 beyond the eyes, with a wide shallow bight instead of the usual notch in the middle, no side 

 lobes, and a shallow median furrow ; the anterolateral edge with three low, blunt teeth, the 

 hindermost of which is hardly distinguishable ; the chelipeds, large, unequal, covered with granules 

 of some size, which are largest on the upper part of the outside of the hand, no spines on the 

 arm or wrist, the fingers flattened, not gaping, sharply pointed at the tips, in the large hand 

 the fingers set, on their opposed edges, with a row each of conical teeth, in the small hand 

 these edges blade-like, making up a remarkable pair of shears, which are no doubt adapted 

 to some peculiarity in the habits ; and the walking legs rather slender, each bearing on its 

 last joint a set of three slender, brown end-claws, of which two are somewhat smaller than 

 the third." 



Length : 3 mm. Breadth : 4 mm. Colour in spirit : pale brown, the walking legs white, 

 the back covered with small dark-brown spots, the fingers white. 



One female specimen taken on Leptoria tenuis in Minikoi lagoon. 



Subgenus Platyozius, n. 



A specimen dredged in Suvadiva cannot be refeiTed to any known species, and is also 

 difficult to place in a genus. It differs from Pseudozius, as hitherto defined, in more than one 

 point, but none of these is of importance enough to warrant the setting up of a new genus, 

 and it is therefore taken here as the type of a new subgenus Platyozius. Other groups of 

 species akin to Pseudozius will probably have to be reduced to this rank before long. 



Platyozius differs from Pseudozius s. str. in the following points: (1) Relatively greater 

 fronto-orbital breadth. (2) Absence of small outer lobes from the front. (3) Equality of the 

 chelipeds. (4) Slenderness of the legs. (.5) A flatter and shallower body. (6) Less marked 

 endostome ridges. 



5. Pseudozius {Platyozius) laevis, n. sp. (Fig. 45). 



Diagnosis : " A Platyozius with the carapace smooth, hairless, without regions ; the front 

 broad, bent slightly .downward, almost straight, with a broad shallow bight in the middle and 



1 See above, footnote to p. 239. 



