419 



rami considerably reduced in number. Last pair of legs comparatively small, 

 foliaceous, distal joint well defined or in some cases confluent with the proximal one. 

 Remarks. In this new genus I propose to include 4 species, 2 of which 

 have been previously described, but erroneously referred to as many known genera. 

 One of these, not yet examined by myself, is Mesochra Macintoslii, Th. 

 Scott, the other Normanetta attenuata, A. Scott. These 2 species are undoubtedly 

 congeneric, but certainly cannot be referred either to the genus Mesochra 

 or to Normanetta, differing, as they do very materially, from both these genera. 

 A new genus is therefore required to include these 2 species as also 2 new ones 

 to be described below. The generic name here proposed refers to the extremely 

 slender form of the body and the delicate structure of the several appendages. 



Leptomesoehra attenuata, (A. Scott). 



(Suppl. PI. 41). 



Xormanella attenuata, A. Scott, Description of some new and rare Copepoda from Liverpool Bay. 

 Report on the Lancashire See-Fisheries Laboratory f. 1895, p. 16, PI. IV, figs. 8 20. 



Specific Characters. Female. Body very slender and elongated, cylindrical 

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

 segment about the length of the 2 succeeding segments combined, and not very 

 deep; rostral prominence very small, knob-like. Urosome unusually elongated, 

 being even longer than the anterior division, and having the segments per- 

 fectly smooth, genital segment rather large, last segment exceeding in length 

 the preceding one and somewhat narrowed distally, anal opercle comparatively 

 small and perfectly smooth. Caudal rami a little longer than they are broad, and 

 slightly tapering, apical setse rather slender, the inner medial one equalling in 

 length the urosome. Anterior antennse slender and narrow, exceeding half the 

 length of the anterior division, and composed of 8 joints, the 2nd of which is the 

 largest, 3rd joint somewhat longer than 4th, terminal part scarcely attaining the 

 length of those two joints combined. Posterior antennae with the outer ramus bi- 

 articulate, distal joint however extremely small and tipped with a single seta. 

 Mandibular palp comparatively large, with the basal joint fusiform in outline and 

 carrying outside, close to the base, a very small knob-like outer ramus. Anterior 

 lip conically tapered. 1st pair of legs rather small, outer ramus considerably 

 shorter than the 1st joint of the inner, its terminal joint somewhat smaller than 

 the middle one, and armed at the end with 2 spines and 2 geniculate setae; inner 

 ramus biarticulate, with the proximal joint long and slender, carrying inside, in 

 front of the middle, a ciliated seta, distal joint comparatively small, with a claw- 

 like spine and a moderately long seta at the tip. The 3 succeeding pairs of legs 



