493 



curved. Last pair of uropoda about as in A. liomari, being however edged 

 with a smaller number of spines and setae. Telson oval quadrangular in 

 form, scarcely longer than it is broad at the base, and not nearly reaching 

 to the end of the basal part of the last pair of uropoda, tip slightly emarginated 

 in the middle, and armed, on each side of the emargination, with a slender 

 spine. Colour yellowish, mottled with reddish brown. Length of adult female 

 scarcely exceeding 10 mm. 



Remarlis. This species was first distinguished from the preceding 

 one by Rathke, but has been subsequently regarded by most authors as only 

 a smaller variety of it. Boeck however maintained the species, and 

 I have myself come to the same result. Besides by its much inferior size, 

 it may be easily distinguished from A. liomari by the want of distinct dorsal 

 projections, whereas the latter in equal-sized specimens of A. liomari 

 are fairly conspicuous. Moreover the antennae and pereiopoda are 

 comparatively shorter and stouter, and the telson of a rather dif- 

 ferent form. 



Occurrence. The species is not uncommonly met with along the 

 whole south and west coasts of Norway, at least to the Trondhjemsfjord, 

 and is generally found close to the shore, in company with Cdlliopius Ratlikei, 

 which it "strongly resembles both in habits and external appearance. 



Distribution. British Isles (Sp. Bate), Kattegat (Meinert), coast 

 of France (Chevreux). 



Gen. 4. Gammaracanthus, Sp. Bate, 1862. 



Body comparatively slender, with the back distinctly carinated 

 throughout, the carina being in most of the segments elevated to distinct 

 dorsal projections. Cephalon produced in front to a greatly projecting 

 acuminate rostrum, lateral corners very small. Coxal plates not very deep; 

 4th pair scarcely emarginated posteriorly; 5th and 6th pairs distinctly 

 bilobate. Eyes distinct, though small. Superior antennas rather slender, 

 with a well-developed accessory appendage. Inferior antennae much smaller 

 than the superior, and rather feeble Oral parts of normal structure. 

 Gnathopoda rather elongated., and in both sexes provided with strongly 

 developed subcheliform hands. The 2 anterior pairs of pereiopoda of moderate 

 length; the 2 succeeding pairs very slender and elongated, with the basal 

 joint comparatively narrow, last pair much shorter than the 2 preceding 



