142 



which in the male are greatly developed, whereas the ventral eye is of the same 

 appearance in both sexes. Moreover, the last segment of the metasome is con- 

 fluent with the preceding one, and the inner ramus of the 1st pair of natatory 

 legs is biarticulate, like that in the other pairs. Finally, the structure of the 

 last pair of legs is somewhat different in the 2 sexes, the chela of the right leg 

 in male being exceedingly large and powerful. We know at present of numerous 

 species belonging to this genus, amounting to about 23 in all. One of these 

 species has been found off the Norwegian coast, and will be described below. 



60. Labidocera Wollastoni, Lubbock. 



(PL XCV & XCVI). 

 Pontella Wollastoni, Lubbock, in Ann, nat. hist. ser. 2, Vol. 20, p. 4<>ii, I'], lo. 11. 



Syn: Pontella helgolandica, (Jlaus. 



fic diameter*. Female. Anterior division of body, seen dorsally, 

 oblong oval in form, greatest width exceeding % of the length, and occurring 

 behind the middle, anterior extremity somewhat contracted and narrowly rounded 

 at the tip, posterior but slightly attenuated. Cephalosome exceeding in length 

 the 3 succeeding segments combined, lateral hooks well marked, rostrum abruptly 

 deflexed, with the rami acutely pointed. Lateral lobes of last segment of meta- 

 some triangular and perfectly symmetrical. Urosome comparatively short and 

 thick, 3-articulate, not nearly attaining l / s of the length of the anterior division, 

 genital segment produced dorsally to a large sacciform expansion turned somewhat 

 to the right, and quite overlapping the succeeding segment. Caudal rami sym- 

 metrical, with the seta3 comparatively short and thick. Dorsal ocular lenses small 

 and widely apart. Anterior antennae very slender, reaching, when reflexed, about 

 to the end of the 2nd caudal segment. Posterior antenme with both rami rather 

 slender, the inner one the longer. Last pair of legs rather robust, both rami 

 well developed, lanceolate, without any denticles or setse, the outer one the larger. 

 Male more slender than female, with the lateral lobes of last segment of 

 metasome shorter and more obtuse. Urosome narrower and perfectly symmetrical, 

 1st segment not produced on right side. Caudal rami more elongate than in 

 female, with the setse rather slender. Dorsal ocular lenses exceedingly large and 

 placed near together. Right anterior antenna with a hook-like projection on the 

 penultimate joint of the middle section and a coarsely serrate lamella on the last 

 one; antepenultimate joint of the terminal section produced at the end anteriorly 

 to a slender, rod-like process. Last pair of legs very asymmetrical, left leg provided 



