512 



at the lateral corners. Eyes small, rounded oval in form, pigment black. 

 Superior antennas equalling about 2 /s of the length of the body, 1st joint of 

 the peduncle fully as long as the 2nd, 3rd joint exceeding half the length 

 of the latter, nagellum nearly twice as long as the peduncle, and composed 

 of about 18 articulations, accessory appendage extremely small and uniarticulate. 

 Inferior antennas scarcely more than half as long as the superior, the last 2 

 joints of the peduncle nearly equal-sized, flagellum not attaining the length 

 of those joints combined. Anterior gnathopoda poorly developed, propodos 

 very small, scarcely more than half as long as the carpus, and subquadran- 

 gular in form, palm distinctly denned and transverse. Posterior gnathopoda 

 in female much stronger, propodos about the length of the 2 preceding joints 

 combined, and oval in form, with the palm nearly transverse, and denned 

 below by a distinct angle armed with 2 slender spines; those in male of a 

 similar structure to those in female, but having the propodos considerably larger. 

 The 3 posterior pairs of pereiopoda rather strongly built, and having the 

 outer part edged with fascicles of slender spines, basal joint considerably 

 expanded and regularly oval in form. Last pair of uropoda about the length 

 of the urosome and the last segment of metasome combined, basal part rather 

 short, outer ramus oblong linear in form, with about 3 fascicles of spinules 

 on either side, tip obliquely truncated, and densely clothed with unequal 

 spines, inner ramus, as usual, very small and scale-like. Telson comparatively 

 small, with the lateral lobes obtusely rounded, and armed at the tip w T ith 

 several short spines. Body whitish, pellucid, without any pigmentary 

 ornament. Length of adult male 6 mm, of female considerably less. 



Remarks. The present form is easily distinguished from any of 

 the other species by its perfectly smooth body, the structure of the gnatho- 

 poda, and the form of the telson. It looks at first sight very like a 

 Gammarus. 



Occurrence. The only place, where I have met with this form, is 

 in a rather large brackish basin, Framvaren, lying between Farsund and 

 Flekkefjord, inside the Listerland. It here occurred rather plentifully 

 among grass, together with Neomijsis vulgaris. Out af Norway, it has not yet 

 been recorded. 



