84 BULLETIN 84, UNITED STATES NATIONAL MUSEUM. 



and wliich came also from the dredgings of the Albatross (station 2573, southeast of 

 Georges Bank, Sept. 2, 1885, 1,742 fathoms). This specimen is in a fairly good state 

 although two arms are broken near the base and none of the other tliree are preserved 

 to their entire length; the diameter of the disk equals 10 mm. 



I shall avaU myself of the opportunity offered me to study tliis species to add a 

 few remarks to Verrill's description and especially to reproduce a few photographs 

 of that form which has never been figured ; it would be, in fact, very difficult to 

 identify it only by the information given by Verrill. 



I wUl first describe the example determined by the latter and afterwards I will 

 compare with it the other examples wliich I have in hand. 



The 10 radial ribs indicated by Verrill are plainly visible. The radial sliields 

 in which they end are quite distinct, though small; they are triangular, a little 

 longer than wide, and bare or carry only a few little stumps near their periphery. 

 The two sliields of each pair are strongly set apart from each other and separated 

 by an interval which is equal to the width of the corresponding arm. The upper 

 face of the disk is covered with extremely tliin, rounded, imbricated, and subequal 

 plates, which become very apparent after they have been freed from the little 

 stumps borne by them. These stumps really have the shape indicated by Verrill. 

 I shall add that they are very short, very much widened at their base, and rather 

 conical ; the spinules which terminate them are rather thick, short, very irregularly 

 arranged, and variable in number. Each plate bears only one such little stump. 



The interradial spaces of the under face of the disk are covered with larger and 

 more distinct plates than on the u])per face, and consequently the stumps are not 

 so dense; they become shorter as they get nearer to the mouth shields. The genital 

 slits are narrow, elongated, and quite distinct. 



The mouth sliields are short and strongly widened transversely; their shape is 

 rather irregular on the specimen from Georges Bank, and the angles are more or 

 less rounded; I observe no median lobe on the distal side. The adoral plates are 

 narrow, elongated, and slightly incurved in the shape of a crescent ; they preserve 

 the same width over their whole length and do not separate the mouth shield from 

 the fii'st lateral bracliial plate. The oral plates are of medium size. The oral 

 papillae, amounting to three on each side, display the characters indicated by Verrill; 

 the external papiUa, especially, is conical and pointed like the others, and even, 

 perhaps, a little smaller than they are. 



The arms are not moniliform. The upper bracliial plates are large, triangular, 

 almost as long as wide, or a little wider than long, with a "f au'ly opened proximal 

 angle limited by straight sides, and a very convex distal edge. On the first 10 or 

 12 articles the proximal angle is rather strongly truncated. These plates are at 

 first contiguous, and afterwards separated by a little interval. 



The first under brachial plate is small, trapezoidal, wider proximally than 

 distally, with a small and rounded distal edge. The following plates are middle- 

 sized, pentagonal, with a very obtuse proximal angle and a convex distal side; they 

 are first much wider than long, and, at a certain distance from the disk, their width 

 slightly decreases, though stUl remaining always wider than long. They are 

 separated by a narrow interval from the base of the ai-ms. 



