311 



17. Monoculopsis longicornis (Boeck) 



(PI. 110, fig. 1.) 

 Monoculodes longicornis, Boeck, Crust, amph. bor. & arctica, p. 85. 



Body of female rather robust, and greatly tumefied in its anterior part. 

 Cephalon scarcely exceeding in length the first 2 segments of mesosome 

 combined, frontal part produced to a very short triangular rostrum, lateral 

 corners nearly rectangular. The 3 anterior pairs of coxal plates compara- 

 tively small and successively increasing a little in size; 4th pair very broad, 

 fully as large as the 3 preceding pairs combined, distal edge evenly curved, 

 infero-posteal corners rather produced ; 5th pair still broader, but not 

 quite so deep. Eyes rounded, pigment light red, with a whitish coating. 

 Both pairs of antennae densely setous; the superior ones about the length of 

 the cephalon and the 4 anterior segments of mesosome combined, 2nd joint 

 of the peduncle very slender and much longer than the 1st, 3rd joint about 

 as long as the latter, flagellum scarcely longer than the last joint of the 

 peduncle, and composed of 8 articulations only. Inferior antennae a little 

 shorter than the superior, last joint of the peduncle exceeding in length the 

 penultimate one, flagellum shorter than those joints combined. Anterior 

 gnathopoda not very strong, basal joint attaining the length of the others 

 combined, propodos oblong oval in form, about twice as long as it is broad, 

 palm very oblique, and about the length of the hind margin, carpal lobe 

 narrowly linguiforin, extending considerably beyond the latter. Posterior 

 gnathopoda much longer than the anterior, and rather slender, propodos 

 nearly 5 times as long as it is broad and considerably narrowed in its outer 

 part, palm scarcely equalling J A of the length of the hind margin, carpal 

 process very narrow, styliform, extending far beyond the latter, its tip nar- 

 rowly blunted. The 2 anterior pairs of pereiopoda having the meral joint 

 rather expanded, and equalling in length the last 2 joints combined, dactylus 

 rather small; the 2 succeeding pairs not very much elongated, basal joint much 

 expanded, meral joint large, dactylus short and broad. Last pair of pereiopoda 

 considerably exceeding half the length of the body, basal joint rather broad, 

 and having the posterior edge smooth and evenly curved, carpal joint about 

 the length of the meral one, and somewhat shorter than the propodal joint, 

 which about equals in length the terminal one. Last pair of uropoda with 

 the rami a little longer than the basal part, narrowly lanceolate, and armed 

 with several small spinules. Telson rounded quadrangular, terminal edge very 

 slightly insinuated. Body whitish, variegated with a pale brownish violaceous 

 pigment dorsally. Length of adult female reaching 9 mm. 



Remarks. The present form was first described by Boeck as a Mono- 



