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scarcely projecting at all between the insertions of the anterior antennae, posterior 

 subtruncate, Avith the lateral corners drawn out to comparatively short and some- 

 what divergent acute projections; seen laterally only slightly vaulted anteriorly, 

 front narrowly rounded and armed below with a very small bifid rostrum. Uro- 

 soine considerably exceeding % of the length of the anterior division, genital 

 segment but slightly dilated. Caudal rami scarcely longer than the anal segment 

 and somewhat divergent, apical setae of moderate length and densely plumous. 

 Eye unusually large and distinctly bilobate, dark red in colour. Anterior antennae, 

 when reflexed, reaching to about the middle of the 2nd caudal segment. Posterior 

 antennae with the outer ramus about Vs longer than the inner. 1st pair of legs 

 with a well-marked setiform spine outside the 1st joint of the outer ramus; 2nd 

 pair with the inner ramus distinctly biarticulate. 



Male - nearly as large as female, but of more slender form ; rostral pro- 

 jection and lateral processes of last segment of metasome about as in female. 

 Urosome, as usual, 5-articulate, with the anal segment shortened, and the caudal 

 rami mobile. Anterior antennae considerably shorter than in female, not nearly 

 so long as the anterior divisions, and somewhat incrassated at the base, con- 

 sisting of 23 articulations, the proximal ones with long band-like sensory appen- 

 dages. Mandibular palps much more strongly built than in female, with the inner 

 ramus well developed and carrying at the tip very coarse diverging setae. Last 

 pair of legs well developed, the right leg being considerably stronger than the 

 left, both with a small unicarticulate appendage inside the 2nd joint, representing 

 a rudiment of the inner ramus, 3rd joint of right leg somewhat curved, and much 

 larger than the others, 4th joint slightly dilated distally, 5th transformed to a 

 slender claw, obtuse at the tip. 



Colour, Body in both sexes pellucid with a faint rosy tinge, intestine 

 in female translucent with a bright red colour, ovarial tubes opaque whitish. 



Length of adult female 4 mm., of male about the same. 



Remarks. This form was recorded in the year 1872 by Boeck as Eu- 

 chceta armata; but the characterisation of the species was very insufficient, for 

 which cause it has not been recognized by subsequent authors, even as regards 

 its generic relation. By comparing the drawings left by that author, however, 

 I have convinced myself that the form here under consideration is the true 

 Euchceta armata of Boeck. On the other hand, the form from Nansen's Polar 

 Expedition, previously described by the present author under this name, has 

 turned out to be a different, though closely allied, species, as subsequently shown. 



Occurrence. Boeck found this form at Skudesnaes, west coast of Norway, 

 at a depth of 300 fathoms. I have myself met with this Calanoid in, great 



