103 



broad than duep. Last pair of epinieral plates of nietasome nearly rectangu- 

 lar, lateral corners drawn out to a very sliort jioint. First segment of uro- 

 some slightly dejtressed dorsally. Eyes comparatively small, I'ounded oval, 

 2)igment red. .Superior antennae in female about the length of the cephalon 

 and the 4 anterior segments of mesosome combined; 1st joint of the i)eduncle 

 more than twice as long as the other- 2 taken together; tlagellum very slen- 

 der, nearly 3 times as long as the peduncle and composed of about 26 arti- 

 culations, the 1st of which is by far tlie largest; accessory appendage scarce- 

 ly exceeding Vi of the length of tlie flagellum and 5-articnlate, 1st joint 

 b)nger than all the others coml)ined. Inferior antennae a little longer than 

 the superior, basal joint large and globular, flagellum composed of about 30 

 articulations. Both pairs of antennae in male having the flagella somewhat 

 longer than in female and composed of a much greater number of articulations. 

 Anterior gnathopoda very powerful, propodos rather broad, quandrangular, 

 and longer than the carpus; palmar edge somewhat obliqiie and armed with 

 several denticles, 2 of which placed below are larger than the rest; dactylus 

 rather strong and quite simple. Posterior gnathopoda witli tlie propodos 

 about half the length of the carpus and oblong in form. Anterior pereiopoda 

 rather j)owerfiil, with the propodal joint curved and the dactylus unguiform; 

 ]iosterior ones much more slender, penultimate pair the longest and having 

 the propodal joint very elongate and narrow. Last pair of uro]ioda with 

 botli rami broadly lanceolate, the inner a little shorter than the outer. Tel- 

 son rounded, scarcely' more long than Inroad, tip very slightly emarginated 

 in the middle and having 2 small denticles. Colour whitish. Length of adult 

 female 13 mm. 



liemarlcs. — The present form, originally described by Kriiyer as an 

 Anonyx, was subseqiiently, as stated above, referred by Sp. Bate to the genixs 

 Alihrofus of Milne-Edwards on account of the unusually elongated antennae 

 and the powerful structure of the anterior gnathopoda, in which respect it 

 certainly differs rather markedly from the genus Oncsimus, to which it was 

 more recently referred by Boeck. 



Occurrence. — I have not myself met with this foi'm off the coast of 

 Norway. But Dr. Goes records its being found b_\' Prof. Fries in the Varan- 

 gerfjord, Finmark. Quite recently, too, Mr. Schneider told me that lie liad 

 procured this form rather plentifully in the neighbourhood of Tromsii by 

 sifting the muddy sand at the low water mark. It thus may in fact l)e 

 regarded as a true littoral form, bui'ving itself in the loose shingle whilst 

 the water retreates. In the Polar Sea it has often been observed in great 

 abundance at the very surface of the water. 



