





974 



CRUSTACEA. 



The genus is near Erichthonius (Edwards), if not identical with it. 

 The stress which is laid by M. Edwards on the rudimentary character 

 of the epimerals of the anterior thoracic segments, and his reference 

 of his species to the Corophidae or gressorial Amphipods, lead us to 

 doubt the identity. The posterior stylets have the same form as in 

 Dercothoe, and the form of the head, the projecting eyes, and general 

 habit, are nearly as in that genus. The approximation is so close, that 

 the genera are evidently of one and the same group ; we have no evi- 

 dence in the antennae, caudal stylets, or legs, that the species in any 

 case are gressorial. The antennae are slender, with long flagella. The 

 epimerals are broader than in some Gammari. The caudal stylets are 

 rather long. 



Kroyer observes that a species of Erichthonius is male of a Podo- 

 cerus, the Podocerus being the female form. If this be a fact, the 

 Erichthonii are quite distinct from the Pyctili. For a female Pyc- 

 tilus, bearing eggs, has been observed by the author, which has the 

 same form of hands as is characteristic of the group Erichthonius. 

 Moreover, the posterior caudal stylets of Pyctilus are unlike those of 

 Podocerus and any related genus. The form in Erichthonius has not 

 been particularly described. 



In this genus as well as the preceding, the first joint of the legs of 

 the fifth and sixth pairs is very broad, while that of the seventh is 

 narrow. 



The name of the genus Pyctilus is from *v*r«<, a boxer, and alludes 

 to the very large and well-formed hands of the species. 



Pyctilus macrodacttlus. 



Corpus gracile, epimeris mediocribus, capite oblongo,f route laterali saliente. 

 Antennas elongatce: 2dce corpore breviores, articulis tertio quartoque 

 subcequis, longis, flagello paulo breviore quam basis, fermd 10-articu- 

 lato, setis perbrevibus. Pedes antici parvidi, rnanu carpoque simul 

 sumtis angusto-ellipticis, breviter Jiirsutis, rnanu breviore quam carpus, 

 digito parvo. Marnis secunda validissima, paulo <*-/orma, digito 

 immobili valde elongato, simplice, acuto, rnanu ultra hujus digiti bwtin 

 elongate productd, digito mobili longiore quam manus, articulis ejus 

 elongatis, subcequis, intus sparsim et breviter hirsutis. Pedes %tii 4=tique 

 subcequi. Pedes 6 postici sensim increscentes, articulo quinti paris 

 primo postice acutd producto. 



