143 



"Challenger", the rostrum was even a little more than twice as long as the carapace : like in 

 Acanthephyra and other genera the rostrum appears the longer the younger the specimens 

 are. The rostrum (Fig. 33 a) runs at first slightly downward as far as the tip of the antennular 

 peduncle, is from here distinctly bent upwards and runs then straight to the tip; the low gastric 

 crest reaches not yet to the middle of the carapace, gradually fading away. The upper margin 

 is armed in the ova-bearing female with 48, in the two other specimens with 45, forwardly 

 directed teeth that reach to near the tip and that are very closely set, their slightly convex, 

 upper border being nearly contiguous to the slightly concave, lower margin of their predecessors ; 

 in the two adult females 5 teeth stand on the carapace, in the young specimen 6, while the 

 6 th , respectively the ; lh tooth stands immediately before the orbital margin. The first 5 or 6 

 teeth gradually increase in size, those that are placed above the basal antennular article, are 

 equal and slightly larger than the following that decrease again in size to the tip ; the distance 

 between the i st tooth and the orbital margin measures one-seventh the leneth of the 

 carapace. The lower margin is armed in the ova-bearing female and in the young specimen 

 with 27, in the other female with 22 teeth; these teeth are a little smaller than those which 

 are placed on the upper margin above the eyes, the i st stands near the tip of the antennular 

 peduncle, while the foremost is placed just posterior to the anterior tooth of the upper margin, 

 at 1,5 mm. from the apex of the rostrum. All the teeth both of the upper and lower margin 

 are fixed, but the first two or three, on the carapace, show a rather indistinct articulation. 



Posterior margin of 3 rd abdominal tergum moderately prominent. In the adult females 

 the 6 th abdominal somite (Fig. 33^, 33*;) is i^-times the length of the 5 lh , in the young 

 specimen the 5 ,h is little more than half as long as the 6 th ; the height of the 

 6 ,h somite anteriorly is al most fi ve-ei g h t hs, its minimum thickness, when 

 looked at dorsally, two-fifths the length. The telson which in the full-grown 

 specimens is al most one and a half as long as the 6 th somite, in the young specimen, 

 however, but one-fourth longer, appears in the adult specimens as long as the endopodite 

 of the caudal fan, but shorter than the exopodite, though the long external, terminal spinules 

 reach as far backward as the exopodite; in the young specimen the telson is a little shorter. 

 There are three pairs of small dorso-lateral spinules on the telson, of which the 2 nd pair is 

 twice as far distant from the anterior than from the posterior pair. 



Though the small circular ocellus is quite separate from the eye, the pale ring that 

 surrounds it, is for a short distance in contact with the cornea. 



The antennular peduncle reaches hardly more than one-third along the antennal scale, 

 3 rd joint of the peduncle a little longer than 2 nd , stylocerite acute, as long as basal article; 

 antennular flagella nearly as long as the body, rostrum included. 



Antennal scale one-fifth shorter than the carapace, narrow and tapering, terminal spine 

 of outer margin reaching a little beyond the truncate tip of the lamella-, flagella one and a 

 half as" long as the body, rostrum included. 



The external maxillipeds extend by a little more than their terminal joint beyond the 

 scaphocerite and the exopodite reaches about to the middle of the antepenultimate joint. 



The legs of the i st pair, a little longer than the external maxillipeds, project by the 



