ICHTHYOLOGICAL COLLECTIONS OF THE ALBATROSS. 4138 
series of dorsal plates is accompanied above by a more or less irregular row of 
smaller plates, which alternate with the larger plates and bear each a small spine. 
_ Head 3 to 3} in length; depth 6. Caudal peduncle long and very slender, its 
depth less than one- aie its length. Maxillary reaching to or nearly to vertical 
from middle of orbit, 22 to 2% in length of head. Jaws weak; teeth villiform, with 
widened base, in nace bands on jaws, vomer, and poland Nasal spines strong, 
projecting above a transverse depression which crosses snout immediately in front of 
orbits. Interorbital space narrow; its least width 33 times in orbit, its width wholly 
occupied by the two conspicuous supraorbital mucous canals. Occiput a shallowly 
depressed pit, bounded anteriorly by the raised orbital region and laterally by low, 
sponded ridges, each of which terminates behind in a very strong spine. Preopercular 
ines slender and sharp, the uppermost directed very obliquely upward, sharply 
BBichea at tip. The second and third are directed downward and backward, the 
lowermost downward and forward. The bony stay across cheeks is conspicuously 
developed, and bears a distinct spine just behind eye. A series of mucous slits 
along under side of suborbital stay. A sharp spine on subopercle. Gill-membranes 
broadly united, free from the isthmus. Branchiostegals,6. A distinct slit-like pore 
behind fourth gill. Eye large, 3 in head, longer than snout. Top and sides of head 
with many minute scattered whitish pores. A minute filament near tip of maxillary. 
_ Plates of lateral line 43 to 46 in number, their upper and posterior edges free, 
denticulated. Dorsal series with 45 plates, each of which is crossed obliquely by a 
raised spiny ridge, the central portion of which is highest. Between the upper 
angles of these plates is a second series of small plates alternating with the first, 
each bearing a spine or prickle. These spines are occasionally doubled or trebled, 
especially in the anterior part of the series, and then recall strikingly the arrange- 
ment in Icelinus. Axil of pectorals with from 20 to 26 plates similar to those of the 
lateral line and showing a tendency to regular arrangement. Two or three similar 
plates along anterior part of base of anal, and a few scattered plates on each side 
between lateral and dorsal series. 
Dorsal vu or vit, 23 or 24; anal 19; pectoral 16; ventral 1,3. Lateral line 43 to 
46. Length 110 mm. 
Color: Light olivaceous above, blackish below, except lower jaw; back with four 
black crossbars, evident but not conspicuous. Opercles black. Fins alldark. Pecto- 
rals mottled with slate color. Base of caudal finlight. Mouth and gill-cavity dark. 
The types were taken north of Unalaska, at station 3329, at a depth of 399 
fathoms. 
54. Icelus vicinalis sp. nov. 
This species is extremely close both to J. canaliculatus, with which it was found 
associated, and to J. ewryops Bean. From J. canaliculatus it differs in the following 
respects: 
(a) The coloration, though similar in pattern, is much lighter. The belly is 
dusky, but not deep brown; the isthmus usually becomes abruptly white under 
the branchiostegal membranes, and the latter are white or dusky, not blue-black as 
in J. canaliculatus. The floor and anterior part of the roof of the mouth and the 
gill-cavities are white, not blackish. The nostril tube is white, not black. 
(6) The occipital ridge is lower and less conspicuous and the spines shorter, but 
both are obvious. The small spinous point on suborbital stay is less developed. 
(c) The dorsal spines are 9 in number in all our specimens. 
(d) A closely crowded series or narrow band of prickles accompanies the dorsal 
series, as in J. canaliculatus. It is noticeable, however, that those of the series which 
dcupy a position corresponding to the interspace between the dorsal plates are 
somewhat enlarged, and recall the alternating plates of JIcelinus. The region 
between the lateral line and the dorsal series is almost completely invested with 
spinous scales in most specimens, while in J, canaliculatus few or none are present, 
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