415 



Evansia incerta, Scott. 



(Suppl. PI. 39). 



Tetragoniceps incerta, Th. Scott, Additions to the Fauna of the Firth of Forth, Part I , . 

 10th Ann. Rep. of the Fishery Board for Scotland, p. 254, PI. XII, figs. 117. 



Specific Characters. Female. Body slender, cylindric in form, with the 

 anterior division scarcely broader than the posterior. Cephalic segment com- 

 paratively short, but rather deep, with the lower edges angularly curved in the 

 middle; rostrum rather small, but well defined, and acutely produced at the tip. 

 Urosome nearly as long as the anterior division and having the segments quite 

 smooth, the genital one of moderate size and not subdivided, last segment about 

 the length of the preceding one. Caudal rami almost as long as the anal seg- 

 ment and gradually tapered distally, each exhibiting dorsally in front of the 

 middle a short dentiform prominence accompanied by a delicate bristle, outer 

 edge with 2 successive slender setas, apical seta having the proximal part remark- 

 ably strong, spiniform, and sharply defined from the thin hair-like terminal part. 

 Anterior antenna? slender, considerably exceeding in length the cephalic segment, 

 and composed of only 7 joints, the first 2 of which are much larger than the 

 others and of about equal length, terminal part about the length of the 2 

 preceding joints combined. Posterior antennae moderately strong, with the distal 

 joint widening somewhat distally, outer ramus very small, with 2 bristles at the 

 tip. Mandibular palp with the proximal joint narrow linear in form, with a small 

 seta at the inner distal corner, distal joint short curved. 1st pair of legs with the 

 outer ramus very narrow and much shorter than the proximal joint of the inner, 

 the latter linear in form and carrying inside, near the base, a delicate seta, distal 

 joint of this ramus quite short and armed at the tip with a claw-like spine and 

 a somewhat longer seta. The 3 succeeding pairs of legs with the outer ramus 

 comparatively narrow and without any setae inside, inner ramus very small, with 

 2 seta) at the tip, and in 4th pair with 2 additional seta3 on the inner edge. 

 Last pair of legs forming each a small triangular lamella terminating in a strong 

 spine and having outside 3, inside 4, slender bristles. 



Male with the anterior antennae strongly hinged, 4th joint considerably 

 dilated and projecting angularly in front. Inner ramus of 3rd pair of legs 

 conspicuously transformed, biarticulate, proximal joint imperfectly defined from 

 the basal part and produced at the end inside to a strong deflexed spiniform 

 process. Last pair of legs with the apical spine not defined at the base, inner 



