122 BULLETIN OF THE 
like arm-spine, which is found only on the first two or three joints beyond 
disk, and stands half-way up the side arm-plate. The second pair of mouth- 
tentacles protrude from very large oval pores covered with four flat rounded 
scales ; the next pores, those of the first arm-tentacles, are similar but smaller; 
the next still smaller ; while those of the fourth under arm-plate are little round 
holes covered by a single scale. Farther out on arm the pores lie behind and 
above the rudimentary under arm-plate. Color in alcohol, white. 
The large side arm-plates and few disk-plates suggest that this is a young 
animal. Unfortunately the depth is given as 18 and 240 fathoms; but the 
character of the animal seems to indicate the latter depth. 
Station 172, off Nukualofa, Tongatabu, 18 and 240 fathoms, 2 specimens. 
OPHIERNUS * gen. nov. 
Central portion of disk inside radial shields covered by a thick skin ; round 
the margin a broad band of scaling, interrupted only by radial shields, and cov- 
ering also the lower interbrachial space, the whole more or less hidden by the 
skin. Radial shields naked. Teeth, and small, numerous, close-set mouth- 
papille. First under arm-plate rather large, and bearing some of the scales of 
the second pair of mouth-tentacles, Upper arm-plates covering the whole 
width of arm. Small smooth arm-spines, arranged along outer edge of side 
arm-plate. Two large, long genital openings in each interbrachial space. 
In the size and function of the first under arm-plate, and in the size and 
shape of the upper arm-plates, this genus has a slight relation to Ophioglypha. 
Ophiernus vallincola sp. nov. 
Plate VI. Figs. 170-172. 
Special Marks. — Three small cylindrical pointed arm-spines, less than half 
as long as an arm-joint, set close together and low down on side arm-plate ; 
mouth-shields rounded and widely separated. 
Description of an Individual (Station 78).— Diameter of disk 9 mm. 
Length of arm about 50 mm. Width of arm close to disk, without spines, 
1.7 mm. Four small, short, rounded, bead-like mouth-papillo on either side of 
the mouth-frames, and usually two at apex under teeth, which are four in num- 
ber; large and flat, with a rounded cutting edge ; besides these there are two 
little papilla on the side mouth-shield and two on the first under arm-plate, 
which may be considered scales of the second pair of mouth-tentacles. Mouth- 
shields triangular, length to breadth about equal, with blunt angle inward, and 
outer corners rounded. Side mouth-shields short, broad without, pointed 
within, lying on lateral sides of mouth-shield, by which they seem widely sepa- 
rated, but the inner narrow points run under the thick skin, and nearly meet 
* pus, snake ; ëpvos, sprout. 
