215 



manner in which it was at first characterised. Thus Dr. Giesbrecht was quite 

 unable to distinguish it from the genus Nitocra, and the form recorded by Prof. 

 Brady as Ameira longipes Boeck, is not an Ameira at all, as clearly shown by 

 the structure of the mandibular palp. Th. Scott also did not recognise the exact 

 limits of this genus; for among the numerous species described by him there are 

 some which unquestionably ought to be discarded and transferred to other genera. 

 In the restriction here adopted the present genus is chiefly distinguished from 

 Nitocra by the less coarsely spinulose caudal segments, the perfectly smooth anal 

 opercle, as also by some well marked differences in the structure of the antennae, 

 oral parts and legs mentioned in the above diagnosis. Although, as above stated, 

 several of the species referred to this genus by other authors must be discarded, 

 there still remain a number of nearly-allied species, which may be regarded as 

 true Ameiras. Some of these will be described in the following pages. 



136. Ameira longipes, Boeck. 



(PI. CXL). 



Ameira longipes, Boeck, Oversigt over de ved Norges Kyster iagttagne Copepoder. Chr. Vid. Selsk. 



Forh. 1864, p. 273 (not Brady). 



Specific Characters. Female. Body moderately slender, with the 2 chief 

 divisions of almost equal length. Last caudal segment scarcely shorter than the 

 preceding one. Caudal rami short, quadrangular, finely ciliated inside, apical setae 

 rather slender and elongated. Anterior antennae scarcely as long as the cephalic 

 segment, 2nd joint much the largest and rather dilated, terminal part about half 

 the length of the proximal one. Mandibular palp with 2 setae inside the basal 

 joint, the outer one very delicate and fringed with long cilia. 1st pair of legs 

 with the outer ramus rather narrow, and scarcely more than half as long as the 

 inner, spines of outer edge comparatively slender and elongated ; inner ramus with 

 the 1st joint more than twice as long as the other 2 combined and having the 

 seta of the inner edge somewhat remote from the end, last joint narrow linear 

 in form and about twice as long as the preceding one. Natatory legs of normal 

 structure, with the 2 proximal joints of inner ranms rather broad. Last pair of 

 legs with the distal joint of moderate size, somewhat dilated at the base and 

 narrowed towards the end, inner expansion of proximal joint extending somewhat 

 beyond the middle of the distal joint and provided with 4 marginal setae, the 

 outermost but one much elongated. 



Male much smaller than female and easily recognisable by the strongly 

 hinged anterior antennae. 1st pair of legs with the spine attached inside the 2nd 



