76 BULLETIN OF THE 
curved, Disk high, covered with rather thin, irregular, curved plates, among 
which may be seen a central five-sided primary, and a large wide plate on the 
margin of the disk, much broader than long. Radial shields rudely semi- 
circular, and meeting only at their outer points, diverging inward, where they 
are separated by a small triangular plate. The interbrachial space on the 
under surface is covered by the rather long and narrow genital scales, which 
are broken in two, and bear no papille, and by two large irregularly curved 
plates, between which and the mouth-shield are from one to three little scales. 
Arm-spines three, short, very small, conical, situated half-way on the outer 
edge of the side arm-plate. Tentacle-pores, except the first pair, small and 
narrow. The first bears about three scales on each side; the second, the 
same ; the third, two ; and the fourth, one minute scale on the outer add two 
on the inner side. Color in alcohol, disk pale gray, arms white. 
Station 224, 1850 fathoms, 1 specimen. 
Ophioglypha costata sp. nov. 
Plate IV. Figs. 92-94. 
Special Marks. — Three very short, blunt, peg-like arm-spines, evenly spaced. 
Disk-scales few and large. Radial shields long and separated. Papillæ of 
arm-comb close-set, flat, and with rounded ends. 
Description of an Individual (Station 142),— Diameter of disk 6.5 mm. 
Width of arm close to disk 1.3 mm.  Mouth-papillo five or six on each side, 
short, square, close-set, with one larger, diamond-shaped, at apex of jaw. Mouth- 
shield five-sided, with outer edge curved, lateral sides nearly straight, and 
an obtuse angle within ; length to breadth 1:1. Side mouth-shields rather 
short, lying along inner angle of mouth-shield, meeting within. First under 
arm-plate broad triangular, with an angle within and curved outer edge; the 
rest are pentagonal, broader than long, with an obtuse angle within, short 
lateral sides, and a long curved outer edge. Side arm-plates a little swollen 
and constricted at their inner end, meeting below ; separated above for the 
first three joints by the upper arm-plates, of which the first is transverse oval ; 
the second four-sided, with a curved outer edge much wider than the inner ; 
and the rest triangular, with an angle within and curved outer edge. Disk 
rather flat, and covered by angular plates and a few small rounded scales, 
closely overlapping ; in centre a five-sided rosette of primary plates, which are 
rounded and partly separated by minute scales ; in the interbrachial spaces a 
single or double row of larger arid smaller plates. Radial shields rhomboidal, 
with the angles slightly rounded ; length to breadth 2: 1; separated without 
by a large diamond-shaped plate, with its outer and inner angles truncated, 
The lower interbrachial spaces have a large marginal plate and four or five 
smaller ones ; genital scales wide, bearing on their free edge a close-set row of 
fine papille, which grow somewhat larger and more rounded above to form the 
arm-comb. "Three arm-spines, minute, blunt, and equally spaced. Tentacle- 
scales short and squarish, five on one side and three on the other of the pores 
