97 



caudal rami not much produced, setae of the latter reduced in number. Anterior 

 antennas in female of moderate size, and clothed with scattered simple setae; 

 those in male much larger and very strongly hinged. Posterior antennas with 

 the outer ramus well defined, though only composed of a single joint. Mandi- 

 bles rather coarse, with the palp distinctly biramous. Maxillae without any 

 distinctly defined exopodal and epipodal lobes. Anterior maxillipeds with 3 

 well defined setiferous lobes inside the basal part. Posterior maxillipeds ex- 

 tremely slender and narrow. 1st pair of legs with both rami short, biarticulate' 

 the 3 succeeding pairs with the rami distinctly 3-articulate, but of rather unequal 

 size. Last pair of legs represented by two undivided juxtaposed plates, which 

 in male are coalesced in the middle. 



Remarks. As the name Euterpe, originally assigned to this genus by 

 Glaus, had been preoccupied in Entomology, the above slight change of the 

 name has been proposed by the Canon Norman. The genus is somewhat 

 allied to Tachidins, differing however in some particulars rather markedly, 

 especially as regards the structure of the posterior maxillipeds and the 1st pair 

 of legs. It comprises as yet only a single species, to be described below. 



78. Euterpina acutifrons, (Dana). 



(PI. LXVIII). 



Haipacticus? acutifrons, Dana, Crustacea of the Un. St. Expedition, p. 1192, PI. 83, figs. 11 a b. 



Syn: Euterpe gracilis, Glaus. 



Specific Characters. Female. Body comparatively slender, with the 

 anterior division conspicuously broader than the posterior and evenly vaulted 

 above. Cephalic segment occupying about half the length of the anterior 

 division, and gradually exserted in front to a greatly prominent rostral pro- 

 minence, acute at the tip. Lateral parts of the succeeding segments not 

 expanded. Last trunkal segment much smaller than the preceding one. Uro- 

 some not nearly attaining half the length of the anterior division and rather 

 narrow, tapered distally, with the segments minutely denticulated at the hind 

 edges; genital segment about the length of the 2 succeeding segments combined 

 and imperfectly subdivided beyond the middle; last segment scarcely shorter 

 than the preceding one, with the anal opercle finely denticulated at the edge. 

 Caudal rami only slightly longer than they are broad and not at all divergent, 

 each ramus provided near the base with a small subdorsal bristle and at the 

 transversely truncated extremity with 2 rather strong setae of unequal length. 

 Anterior antennae about half as long as the cephalic segment and rather narrow, 



