124 BULLETIN OF THE 
Ophioceramis )۱( 4 
Plate VI. Figs. 161-163, 
Special Marks, —- Four arm-spines, the two upper slender and tapering, the 
two lower stout and blunt. A great marginal scale, which occupies also most 
of the lower interbrachial space. 
Description of an Individual (Station 170). — Diameter of disk 4 mm. 
Length of arm about 18 mm. Width of arm without spines 1.2mm. Three 
short, stout, pointed mouth-papille, well separated on each side, with one 
larger and spearhead-shaped at the apex of angle. Mouth-shields broader 
than long, transverse diamond-shape, with outer angle indented ; length to 
breadth .6:1. Side mouth-shields very large and wide, somewhat longer 
than wide, square without, meeting broadly within, and there forming a deep 
angle. First under arm-plate broader than long, rounded ; the rest are widely 
separated, twice as broad as long, with outer edge nearly straight, a very 
obtuse angle or weak curve within, and a small re-entering curve on the 
lateral sides. Side arm-plates stout, flaring a little outward where they form 
the spine-ridge, meeting broadly above and below. Upper arm-plates broader 
than long, wide fan-shape with an angle inward, somewhat swollen, making 
the arm high and rounded, Disk round and flat, covered with thin, flat, angular 
scales arranged symmetrically ; central primary plate pentagonal, surrounded 
by five others rounded hexagonal and somewhat smaller; interbrachial spaces 
filled by three large scales, the two inner ones four-sided, the outer one rounded 
and lying on the margin, showing little above, but beneath occupying the 
whole interbrachial space except two small scales outside the mouth-shield. 
Radial shields regular, longer than broad, wide without, coming by curved 
sides to a point within, where they are separated by a small triangular scale, 
but are joined for the rest of their length; they, as well as the other disk- 
scales, bear a few microscopic tubercles, Four arm-spines ; the two upper thin 
and tapering, and nearly as long as an arm-joint; the two lower shorter, 
stouter, and more blunt ; towards tip of arm there are three, the upper long 
and slender, as long as two joints ; the second similar, but shorter ; and the 
lowest very stout and somewhat curved. One very small rounded tentacle- 
scale, on the first two pairs of tentacle-pores; beyond there are two. Color in 
alcohol, pale brown, 
Station 170, 630 fathoms, 1 specimen. 
Ophioceramis (?) obstricta sp. nov. 
Plate VI, Figs. 164 - 166. 
Special Marks. — Vive short, nearly equal, blunt, tapering arm-spines. 
Radial shields separated in the brachial spaces, but touching in the inter- 
brachial. 
Description of an Individual (Station 192). — Diameter of disk 4 mm. 
