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28. Tharybis macrophthalma, G-. 0. Sars, n. sp. 



(PL XLV & XL VI). 



Specific Characters. Female. Anterior division of body, seen dor sally, 

 regularly elliptical in form, greatest width equalling about half the length, both 

 extremities almost equally attenuated; seen laterally, much vaulted above, with 

 the dorsal margin forming quite an even curve throughout. Front scarcely at all 

 produced below, tentacular filaments very delicate and reflexed. Lateral parts of 

 last segment of metasome but slightly produced, forming narrowly rounded lobes. 

 Urosome scarcely exceeding in length Vs of the anterior division, genital segment 

 about twice as large as the succeeding one, and slightly protuberant below. Caudal 

 rami a little longer than they are broad, apical setse of moderate length, the 

 innermost but one the longest. Eye very large and conspicuous in the living 

 animal, oblong quadrangular in form, and occurring close to the dorsal face, pig- 

 ment bright red. Anterior antennae, when reflexed, reaching about to the end of 

 the anterior division. Posterior antennae with the inner ramus scarcely half as 

 long as the outer, terminal joint of the latter much the largest. Last pair of legs 

 with the terminal joint more than twice the length of the other 2 combined, nearly 

 straight and of uniform width throughout, exhibiting outside in the middle a small 

 dentiform projection, tip armed with 3 short, thick, denticulated spines, the 

 innermost the largest and distinctly defined at the base, the other 2 confluent 

 with the joint. 



Male somewhat smaller than female, and having the urosome considerably 

 more slender, equalling about half the length of the anterior division. Last pair 

 of legs, when reflexed, reaching far beyond the caudal rami, right leg doubly 

 geniculate, 3-articulate, 1st joint rather thick and forming outside an angular pro- 

 minence, 2nd joint slender, slightly widening distally, terminal joint constituting a 

 claw-like incurved piece; left leg with the 2 basal joints very movably connected, 

 outer ramus 3-articulate, terminating in a bunch of delicate hairs, inner ramus 

 uniarticulate, styliform, and nearly twice as long as the outer. 



Colour. Body in both sexes highly pellucid, with translucent dark yellowish 

 brown intestine. 



Length of adult female 1.40 mm., of male 1.30 mm. 



Remarks. This Calanoid may be easily recognized by its unusually short 

 and robust form, and in the living state, also by the large, dorsally placed, bright 

 red eye. The anterior antenna in the living animal are born in a somewhat 

 unusual manner, exhibiting at the base an abrupt curve, and pointing obliquely 

 backwards. 



