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the sides are best developed in the under part of the valve; the angle the roof forms with 

 the side is greater than 90°. 



The u])per latus is cjuadrangular and rather large. The angle formed by the scutal 

 and basal margins is truncated. The umbo is near the angle the scutal margin forms with the 

 tergal. The carinal margin is the shortest. 



The rostrum is triangular with the apex directed to the base of the scuta. There is 

 a narrow but distinct chitinous interspace between the rostrum and the rostral margins of the 

 ro.stral latera. 



The rostral latus is broad but very low ; the scutal margin runs parallel to the 

 basal margin, the short lateral and rostral margins are both convex. 



The infra- median latus is triangular, the umbo is at the apex which is distinctly 

 curved towards the rostral side of the capitulum: the rostral margin is hollowed out, the carinal 

 margin distinctly convex. 



The carinal latus is pentagonal, the carinal margin being divided into two parts. 

 The upper part is hollowed out, the lower convex. Where they meet the umbo is seated : a 

 pointed and slightly recurved triangular part projects beyond the line of the carina. The basal, 

 lateral and upper margins of the carinal latus are of about the same length. 



The peduncle is cylindrical, bent towards the rostral side. It is broadest where it is 

 attached to the capitulum and is laterally compressed and conical in the upper part. It is covered 

 with a hairy transparent membrane through which the scales are visible. They are placed at 

 some distance from one another and are arranged in seven or eight longitudinal rows. 



Size. The capitulum of the largest specimen had a length of 27 mm. The total length 

 was about 40 mm. 



According to the label the larger specimen of this species was found attached to a 

 specimen of Culeohcs thysanotus Sluit. This was collected at Station 94. The smaller specimens 

 are attached to one another, as also to a small black coloured stick or spine, the nature of 

 which is unknown to me. 



The study of the structure of the animal contained within the capitulum has yielded the 

 following results : 



Mouth seen from above triangular, with the apex of the triangle directed towards the 



adductor muscle; the prominence on which the mouth is situated is not very elevated in this species. 



Labrum with extremely small teeth along the edge; palpi short, broad at the base, 



triangular, with the apex rounded. The inner margin is furnished with numerous hairs growing 



slightly longer and more numerous towards the apex. 



Mandibles with three teeth and the inferior angle; the latter delicately pectinated on 

 both sides, but especially so along the interior margin; a slightly broader spine or small tooth 

 at the tip of the inferior angle. The distance between tooth i and 2 about twice as long as 

 that between 2 and 3, or 3 and the inferior angle. Surface of the exterior jjart with numerous 

 delicate hairs, placed in groups of two or three. 



Maxillae have the edge without distinct notch, but with a little excrescence bearing 

 two spines at the tip at about one fifth of the length of the edge from the inferior angle. 



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