138 BULLETIN OF THE 
breadth .8: 1. Side mouth-shields short and rather wide, meeting within. 
Under arm-plates pentagonal, wider than long, with a very obtuse angle in- 
ward, sometimes modified as a curve ; lateral sides a little re-enteringly curved, 
and outer side gently curved. Upper arm-plates wide fan-shaped, with an an- 
gle inward. Side arm-plates stout, rather prominent, narrowly meeting above 
and below, near base of arm. Disk slightly puffed and wrinkled, closely set 
with small, round, smooth grains, among which, on upper surface, appear a 
few short stout spines ; radial shields and disk-scales hidden by skin and by 
granulation. Seven regular, slender, cylindrical, tapering, not thorny arm- 
spines ; lengths to that of an arm-joint 2.8, 2.5, 2, 2, 1.5, 1.3, 1:.8. One 
pointed, rather large tentacle-scale. Color in alcohol, white. 
A smaller specimen had a disk 6 mm. in diameter with grains, but scarcely 
any spines on it. A young one had a disk 4 mm. in diameter, and arms 
16 mm. long. The disk-grains were rough under the microscope ; the arm- 
spines were proportionately longer, and the side arm-plates more prominent, 
than in the adult ; the outer mouth-papilla was larger than its neighbors, 
Station 171, 600 fathoms, 2 and 2 young specimens, 
Ophiacantha granulosa sp. nov. 
Plate VIII. Figs. 206 - 208. 
Special Marks. — Disk evenly set with smooth grains ; outer ends of radial 
shields naked ; ten smooth slender arm-spines, 
Description of an Individual (Station 201). — Diameter of disk 9 mm. Length 
of arm 42 mm. Width of arm without spines 3 mm. Seven pointed, rather 
stout, nearly cylindrical mouth-papille. Seven teeth, flat, with a rounded 
cutting edge. Mouth-shields small, broader than long, with an obtuse angle 
within, and a curve without ; length to breadth .8 : 1. Side mouth-shields 
large and wide, broader without than within, where they are slightly separated. 
Under arm-plates much wider than long, of a wide axe-shape, with a curved 
edge outward, a lobe or a narrow obtuse angle within, and the lateral sides 
re-enteringly curved. Upper arm-plates rather small, of a wide fan-shape, 
with an angle inward, and lateral sides re-enteringly curved. Side arm-plates 
large and moderately projecting, meeting broadly above, near base of arm, but 
scarcely touching below. Disk slightly puffed, closely and evenly set with 
smooth grains, about four in the length of a mm., which hide the fine disk-scales, 
except in the lower interbrachial spaces. Radial shields covered, except their 
outer ends, which are naked and sunken below the surrounding surface. Ten 
slender, tapering, cylindrical, translucent arm-spines, which are not thorny ; 
lengths to that of an arm-joint 3.2, 3.2, 2.2, 2, 2, 2, 1.8, 1.3, 1.3, 1:1. One 
rather small, blunt tentacle-scale. Color in alcohol, pale reddish-brown. 
A younger specimen, with a disk 4 mm. in diameter and an arm of 18 mm., 
presented no special variations, except that there were only eight arm-spines, 
and the under arm-plates were proportionately smaller. 
Station 201, 82 — 102 fathoms, 8 specimens. 
