110 A HISTORY OF RECENT CRUSTACEA 



appearance of the females, especially in the widening of 

 tl A pleon, which is the first characteristic of sex that would 

 generally be looked for. It follows, therefore, that among 

 the specimens which in old times have been regarded as 

 spurious females many spurious males were beyond doubt 

 included. It is also worth remembering that when the 

 shape of the pleon leaves the sex of a crab ambiguous, that 

 may be taken as an indication that some curious species 

 of parasitic crustacean is likely to be found in some part 

 of the organism. 



A large extension has been given to the family of the 

 Inachidas by recent voyages of deep-sea exploration, and 

 in some instances species which, when first discovered 

 only a few years ago, were naturally supposed to be rare, 

 have since proved to be cosmopolitan. Thus the little 

 Lispognatfius Thomsoni (Norman), a delicate species with 

 long slender limbs, taken at a depth of two or three 

 hundred fathoms in the Faro Channel, and first described 

 in 1873, has since then been taken at much greater depths 

 and at places so wide apart as the Straits of Gibraltar, the 

 neighbourhood of the Cape of Good Hope, and of Sydney 

 in Australia. 



Ergasticus, A. Milne-Edwards, 1881, has two species 

 Ergasticus Clouei, A. Milne-Edwards, and Ergasticus 

 Naresii, Miers. The latter was taken near the Admiralty 

 Isles in the Pacific, and recalls the name of the honoured 

 captain of the Challenger ; the former was found in the 

 Mediterranean and the Atlantic, and the name of the 

 genus founded for it signifies ' a worker ' in remembrance 

 of the French ship, the Travailleur, by which the type- 

 specimen was dredged. Plafymaia Wyville-thomsoni (see 

 Plate IV.), Gyrtomaia Murrayi, Cyrtomaia Suhmi, Eclii- 

 noplax Moseleyi, represent new genera and species in this 

 family instituted by Miers in 1886, in which the specific 

 names have been chosen expressly to associate some of the 

 finest of the Brachyura dredged by the Challenger with the 

 names of its staff of naturalists. Platymaia and Cyrtomaia 

 are also pointed out as of especial interest from their ' being 

 Malayasian representatives of a section of the sub-family 



