81 



to the species here under discussion. It may easily be distinguished from Norman's 

 species by its more robust form, and especially by the great development of the 

 2nd pair of epimeral plates in the female. The colour of the body is moreover 

 rather different in the two species. 



Occurrence. I have taken this form rather abundantly in some places on 

 the west coast of Norway, for instance, at Haugesund, Kopervik and Bukken. It 

 is a sub-littoral form, being found close to the shore on the fronds of Laminaria 

 diyitata at low-water mark. The animal, like the species of Porcellidium, has 

 the power of applying its body very firmly to any objects, so that it can only 

 be loosened with considerable difficulty when alive. After the collecting-vessels 

 have been emptied therefore, the greater number of the specimens remain in the 

 bottles, firmly attached to the sides. On shaking the bottles with some fresh water, 

 however, the specimens very soon leave their hold and can be emptied out with 

 the water. In this manner I was enabled, during my last excursion, to secure a 

 great number of specimens. 



Distribution. British Isles (Brady). 



49. Aspidiseus fasciatus, Norman. 



(PI. XLVIII). 



Aspid'iscus fasciatus. Norman, Last Report on Dredging among the Shetland Isles. Brit, Assoc. 



Report for 1868, p. 298. 



Specific Characters. Female. Very like the preceding species in its ge- 

 neral appearance, but of somewhat smaller size and less robust form of body. 

 Anterior division broadly oval in outline, slightly narrowed both in front and 

 behind. Eostrum somewhat more prominent than in A. littoralis, though exhibiting 

 a very similar form. Epimeral plates of the first 3 free segments of metasome 

 less produced behind, 2nd pair not extending nearly as far as the tip of the 

 succeeding pair; posterior edge of 3rd segment straight, scarcely at all limbate. 

 Last segment of metasome, as in the preceding species, wholly obtected by the 

 fornicate hind part of the 3rd segment. Urosome with the segments somewhat 

 less sharply defined than in A. littoralis. Caudal rami extremely small, but with 

 the apical setae excessively elongated, the innermost but one almost attaining the 

 length of the whole body. Antennae, oral parts and anterior pairs of legs of almost 

 exactly the same structure as in A. littoralis. Last pair of legs, however, differ- 

 ing conspicuously in form; proximal joint less curved, and considerably dilated 

 towards the end; distal joint shorter than the proximal one, and broadly oval or 



11 Crustacea. 



