656 



ranging from 2—20 fathoms, especially on muddy bottom. According to the 

 statements of Kroyer, it is often found attached to the common starhsh 

 (Asterias rubens). 



Distrihution. — British Isles (Sp. Bate), Bohuslan (Bntzelins), Kattegat 

 (Meineit), Dutch coast (Hoek). 



Gen. G. Caprella, Lamark, 1818. ^ 



Body more or less slender, being, in the adult male, as a rule, much 

 more elongated than in female, with the anterior part sometimes enormously 

 prolonged. Cephalosome of moderate length, and having a distinct dorsal 

 impression, indicating the boundary between the cephalon and 1st segment of 

 mesosome. Superior antennae more or less elongated, with the joints of the 

 peduncle in male often lamellarly expanded. Inferior antennae generally 

 densely setoiis posteriorly, with the tiagellum biarticulate. Mandibles without 

 any palps. Mayillipeds with the masticatory lobes scarcely larger than the 

 basal ones, palps very strong. Anterior gnathopoda of the usual structure. 

 Posterior gnathopoda strongly developed, and often very differently shaped 

 in the 2 sexes. The 2 anterior pairs of pereiopoda quite wanting; the 3 

 posterior pairs of equal structure, and generally very strongly built, subcheli- 

 form. Branchial lamellae only present on the 3rd and 4th segments of meso- 

 some. Urosome in female without distinctly defined appendages, in male with 

 a pair of biarticulate limbs in front. • 



Eeniarka — This is the genus at first established, being the type of 

 the family. It agrees with the genus Farnmihus in the absolute waut of 

 mandibular palps and of the 2 anterior pairs of pereiopoda, but differs in the 

 circumstance of the antepenultimate pair being well developed and of same struc- 

 ture as the last 2 pairs. Numerous species of this genus have been described, 

 but a great number of them have turned out to be spurious, on account of the 

 authors not having always been aware of the great sexual difference often met 

 with in the species of this genus. AVhile young male specimens do not differ much 

 from the females, the sexually developed adult male generally exhibits a very 

 different aspect, the anterior part of the body becoming greatly elongated 

 and the posterior gnathopoda peculiarly modified. Moreover there seems to 

 be some variation, both as regards the armature of the body and the structure 

 of the superior antennae. In every case, for the exact definition of the 

 species, both sexes ought to be regarded, as also the amount of variation. 

 Most of the new species established by Boeck are indeed only founded on 



