541 



peduncular joint. Anterior gnathopoda in female with the carpus slightly 

 expanded below, and nearly as long as the propodos, the latter somewhat 

 widening distally, with the palm inperfectly denned, and having below a 

 slender spine, dactylus much longer than the palm, and minutely dentated 

 inside. Same legs in male greatly developed, with the carpus very large, and 

 filled up by strong muscular bundles moving the propodos, its anterior corner 

 produced into a strong acuminate projection having below a secondary tooth, 

 propodos much narrower than the carpus and not nearly as long, being 

 slightly arcuate, with the lower edge deeply concave in the middle, and 

 angularly produced in front, dactylus rather elongated and, when closed, 

 impinging against the secondary tooth of the carpal projection. Posterior 

 gnathopoda in female somewhat smaller than the anterior, and having the 

 propodos rather narrow, oblong linear in form, with the palm very short, and 

 the dactylus extremely small ; those in male comparatively larger, but otherwise 

 of a similar structure to those in the female. Last pair of pereiopoda very 

 much elongated, exceeding half the length of the body, and having at the tip a 

 dense fascicle of slender bristles. Last pair of uropoda with the inner ramus 

 somewhat shorter than the outer, both having a few lateral spinules and 3 

 or 4 apical ones. Telson a little longer than it is broad, lateral edges 

 smooth and evenly curved, tip slightly angular, and having on either side a 

 row of 3 slender spines. Body whitish, often with a light reddish tinge, 

 and more or less densely mottled with dark brown pigmentary spots, forming 

 interrupted bands across the segments and the coxal plates. Length of adult 

 female 9 mm, of male about the same. 



Remarks. The present form was described as early as in the year 

 1843 by Rathke as Gammarus anomalus, and was subsequently referred by 

 Bruzelius to his genus Autonoe. Sp. Bate at first described the same species 

 under another name, viz, Lembos cambriensis, but afterwards he recorded it 

 under the name here given. It is easily distinguished from the other 2 

 Norwegian species by the rather full development of the accessory appendage 

 of the superior antennae, and by the structure of the posterior gnathopoda 



in the male. 



Occurrence. - The species is found not infrequently along the whole 

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

 depths varying from 6 to 30 fathoms, especially where the bottom is muddy 

 and covered by decaying algae. 



Distribution. British Isles (Sp. Bate), Bohuslan (Bruzelius), Kattegat 

 (Meinert), coast of France (Chevreux), Azores (Barrois). 



71 Crustacea. 



