58 



particular genus intermediate between Ameira and Parameira. It is of rather 

 large size, as compared with the other known species. 



Occurrence. Two female specimens of the present form were found 

 in a sample taken at Riser from a depth of about 30 fathoms. 



47. Ameira exilis, Scott. 



(PI. XXXVII). 



Ameira exilis, Scott, Twelfth Ann. Report of the Fishery Board for Scotland, 



Part 111, p. 2-12, PI. X, figs. 1-12. 



Specific Characters. Male. Body exceedingly slender and narrow, 

 linear in form, with the anterior division scarcely broader than the posterior. 

 Cephalic segment about the length of the 2 succeeding segments combined 

 and obtusely blunted in front, rostral projection inconspicuous. Urosome fully 

 as long as the anterior division, with the segments subequal in size and almost 

 perfectly smooth. Caudal rami comparatively short, being scarcely more than 

 half as long as the anal segment; apical setae of moderate length. Anterior 

 antennae about the length of the first 2 body-segments combined, and very 

 conspicuously hinged, the middle portion being considerably dilated; terminal 

 part composed of 3 elongated joints, the last clothed with long curved setae. 

 Posterior antennae with the outer ramus biarticulate, distal joint however very 

 small and less distinctly defined at the base. Mandibles with the palp of 

 unusual size, its proximal joint forming inside a broad lamellar expansion 

 armed with 3 strong, spiniform setae; distal joint narrow, sublinear in form. 

 Maxillae and maxillipeds of normal structure. 1st pair of legs distinctly prehen- 

 sile, the inner ramus being much longer than the outer, with the last 2 joints 

 bent inwards, and combined about the length of the 1st joint; middle joint of 

 outer ramus with a well-defined seta inside, wanting in the other known species; 

 spine issuing from the inner corner of the 2nd basal joint very strong and 

 sub-hamate at the tip. The 3 succeeding pairs of legs of normal structure 

 and rather slender, especially the 4th pah, the outer ramus of which is fully 

 twice as long as the inner. Last pair of legs more fully developed than is 

 generally the case in male specimens; distal joint oval in form and provided 

 with 6 marginal setae, 4 of which issue from the obtusely blunted end, one of 

 the latter (the innermost but one) very much elongated; inner expansion of 

 proximal joint well developed and rather prominent, extending about to the 

 middle of the distal joint, marginal setae 5 in number, the outermost but one 

 the longest. 



