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distinctly segmented, with five pair of ambulatory appendages ; cephalic 

 portion wide, with a constricted neck. 



Proboscis — longer than the body, davate, bent downwards. 



Abdomen — long, slender, subclavate. 



Mandibles — three jointed, chelate, well developed. 



Palps — ten-jointed. 



Ovigerous legs — ten-jointed, terminating in a claw, the last four 

 joints with several rows of non-denticulate spines." 



To these characters may now be added. 



Proboscis movably articulated to the body. 



Genital apertures in both sexes on the second coxa of all the legs. 



The sexes are readily distinguishable by the position of these aper- 

 tures. In the male they are small and lie in the mid ventral line quite 

 close to the distal extremity of the joint. In the female they are much 

 larger, generally with pigmented lips and lie also in the mid ventral line 

 but quite close to the middle of the joint. 



The genus Colossendck of Jarzynsky may be re-defined as follows. 



Body ovoid or elongate with lateral processes close together or 

 widely separated; as a general rule without segmentation. 



Proboscis very large, often much longer than the body and movably 

 articulated to it. 



Abdomen of moderate dimensions, movably articulated to body, 

 subclavate. 



Eyes well developed or absent. 



Mandibles very rarely present, rudimentary. 



Palps very long, ten-jointed, more or less setose. 



Ovigerous legs very long, ten-jointed, the last four joints bearing 

 several rows of spines which usually have dentate margins. 



Ambulatory legs without auxiliary claws. 



To the above characters the position of the genital apertures on the 

 second coxa of every limb might fairly be added. Information with 

 regard to this feature is deficient, Hoek being the only auther who has 

 consistently examined his specimens upon this point. In no less than 

 six species he records these apertures on every limb and in two others 

 he was only able to find them on the two posterior appendages. Four 

 species brought by the Discovery from the Ross sea also exhibit these 

 apertures on all four legs and, from all the available information, it is 

 not unreasonable to assume that they may be developed from behind 

 forwards as sexual maturity is attained. Omitting those species in which 

 the genital apertures have not been recorded Colossendeis agrees with 

 Decalopoda, not only in the number but in their position in the two sexes. 

 As to the presence of mandibles, a satisfactory explanation of their 

 occasional presence is not yet forthcoming. They have been recorded 

 in immature specimens of two species, C. gracilis Hoek and C. angusta 

 G. 0. Sars, but they are by no means a constant mark of immaturity. 

 Möbius has recently described a species, C. gibbosa from the "Valdivia" 



