108 BULLETIN OF THE 
OPHIOMUSIUM, 
TABLE OF KNOWN SPECIES. 
Disk-scales numerous and rather flat, with a 
large one on the margin. Two or three short 
stout arm-spines, Side mouth-shields long and 
large. 
Interbrachial space between radial shields oc- 
cupied by two large plates. Papillæ along gen- 
ital openings extending upward as a small arm- 
comb. Four or five small arm-spines. 
Papille on genital openings extending upward 
, Arms rather slender and taper- | as a ema arm-comb, : Ride mantialteldemall 
ing; cylindrical, or but slightly | and short. Upper arm-plates comparatively 
wavy from the gentle swelling | large, some of the basal ones inclining to hexag- 
of the side arm-plates. Upper | onal, Three or four small arm-spines. 
and under arm-plates persisting i R of 
nearly to end of arm; but no Disk thick. Side mouth-shields and under 
tentacles beyond third or fourth arm-plates much swollen. Outer mouth-papille 
under plate. Mouth-shields | Much larger than inner. Genital papille large 
small. Genital opening bounded and bead-like, Six or seven small arm-spines. 
by small close-set papille, Disk flat, covered with small imbricated 
scales, which are nearly equal, except the mar- 
ginal, which are larger. Upper arm-plates large, 
the basal ones long hexagonal. 
J 
Disk covered by thick skin ;, its upper surface | 
f- 
0. eburneum 
Lym. 
O. serratum, 
O, armigerum, 
O, corticosum, 
0. cancellatum. 
occupied chiefly (and in half-grown specimens 
almost entirely) by radial shields and large pri- 
mary plates, with small scales between. Arms 
even and cylindrical, Four minute rudimentary 
arm-spines. 
O, archaster 
Wyv. Thom, 
M8. 
Several flat angular plates in lower interbrachial space besides the large one 
joining the mouth-shield. Genital scales wide. No under arm-plates beyond the 
second or third. 
Upper disk covered by large swollen radial shields, with minute imbricated 
scaling in centre. Arms wide and thick, with side arm-plates much swollen and 
rounded. Upper arm-plates broad diamond-shape. 
Disk covered by large angular swollen plates, | isk-ple 4 
of which the interbrachial marginal is largest. 1 بر‎ O 
Arms wide and thick, with side arm-plates much 
swollen and rounded, and bearing a spine on Upper disk-plates smooth, 
their upper surface. 
0, Lymant 
Wyv. Thom, 
0. laqueatum. 
0. acuferum 
arge tubercles. Lym. 
0. Lütkeni. 
Four small, equally spaced arm-spines. Small upper 
arm-plates. The great lower interbrachial plate has usually 
two much smaller at its outer corners. 
Two minute arm-spines set low down. Besides the great 
Most of the lower | interbrachial plate below, there are three others along the pO. simplex, 
interbrachial space ( ۰ 
outside the mouth- Two minute arm-spines set back from edge of plate. yo hinare. 
shield is oceupied | Only one lower interbrachial plate. No upper arm-plates. : E 
0, validum 
Ljn. 
by broad  genital4 ‘Three short, stout, well-defined arm-spines. Disk-plates 
scales and a great | thick, separated by narrow grooves, and arranged above 
— apa Len like steps. Side arm-plates flaring a little outward. 
yond the third, x Two or three minute arm-spines.  Disk-plates coarse, 
swollen, and irregular. Two or three marginal plates be- 
sides the central one in the lower interbrachial space. 
po scalare. 
Five short, sharp, well-marked arm-spines. The from } 
O, testudo 
Lym. 
lower interbrachial plate is separated by a square one from 0. gramoswm. 
the mouth-shield. Margin of disk set with small points. 
Genital scales meeting on me- 
dian line of lower interbrachial 
space, 
0. pulchellum 
Basal side arm-plates very flat and wide, en- 
Wyv. Thom, 
croaching much on the interbrachial space, and 
bearing stout spines on their outer edge. First Fi m 1 
under arm-plate similar to those beyond, and irst side arm-plates meeting 
furnished with a tentacle-scale. in median line of lower inter- 
0. flabellum. 
brachial space. 
