FISHES OF HAWAIIAN ISLANDS. 
599 
Teeth on jaws and palatines in very narrow bands; broad bands investing the mesopterygoids; 
head of vomer bearing on each side a strongly protruding lobe, devoid of teeth, the concave interspace 
bearing minute asperities; gill-rakers long and slender, 4+14 in number on outer arch; preopercular 
margin vertically placed and evenly rounded. 
Insertion of first dorsal ray slightly behind the vertical from base of ventrals, the last dorsal ray 
vertically over the first anal ray; adipose dorsal over second postero-anal photophore, well in advance 
of last anal ray; pectorals very long and pointed, their tips reaching vent and extending beyond tips 
of ventrals. 
Scales thin, with entire edges, and caducous, occasional scales only being preserved in our material. 
Arrangement of photophores: Agreeing with M. reinhardlii in the obtuse-angled triangle formed 
by the 3 supra-anals, in the presence of 2 posterolaterals, in the wide separation of the 2 caudals, 
and in the njrmal position of the supra-ventral. A minute preocular present on lower anterior 
orbital rim, similar to other photophores, but much smaller; first and second, and second and third 
pairs of thoracic photophores more widely separated than the others, the third and fourth pairs nearer 
together than the others; upper pectoral spot immediately below third scale of lateral line; supra- 
ventral on a level with middle pectoral and middle supra-anal spots, and constantly a little above ante- 
rior supra-anal; upper supra-anal, upper posterolateral and upper caudal spots in contact with lateral 
line at 18th, 26th, and 40th scales, respectively; lower posterolateral in advance of upper, and very 
slightly in advance of last antero-anal. 
The number of photophores is as follows: Preoculars 1; mandibulars 3; operculars 2, the lower 
not concealed; pectorals 3, the middle one immediately below the base of lowest pectoral ray, the 
lower one on a line joining the middle pectoral and the lower opercular spots; thoracics 5, those of the 
last pair more widely separated; ventrals 4, the third and fourth pairs less widely spaced than the 
others; anals 6 to 8+6 to 8 (13 to 15); caudals 2; supraventrals 1; supra-anals 3; posterolaterals 2. 
The anals form the only variable groups. In the 17 specimens (giving 34 cases) of the collection, 
we find them distributed as follows: Antero-anals 6 in 14 cases, 7 in 18 cases, 8 in 2 cases; postero- 
anals 6 in 2 cases, 7 in 23 cases, 8 in 9 cases. In both groups then, the mode is 7, the anterior group 
varying principally toward 6, the posterior group toward 8. The totals of the 2 groups, in the 34 cases, 
are as follows: 13 in 7 cases, 14 in 25 cases, 15 in 2 cases. In the type there is a well-developed luminous 
patch on the lower side of the caudal peduncle, and an incipient patch on the dorsal surface. 
General color dark, with bluish reflections from opercles and scales on sides; caudal with a dusky 
patch at base of each lobe; other fins translucent. 
Specimens were taken at the following stations: Nos. 3878, south of Lanai; 3927, west of Niiliau; 
3980, south of Oahu; and 4145, west of Niihau; all at the surface. 
Named for Dr. August Brauer, the author of a most useful review of the genus Myctophum. 
Dasyscopelus spinosus (Steindachner). 
Forty-nine specimens, the longest 69 mm., were taken at the surface about the Hawaiian Islands, 
and in the vicinity of Laysan Island. They agree in all essential features with the excellent descrip- 
tions and figures cited below. The pectoral fins are a little longer and more pointed than previously 
represented, reaching with their tips a little beyond the ventrals, but not quite to vent. The scales of 
the lateral line are little longer than the neighboring scales. They are almost wholly concealed by 
the overlapping series above and below, the scales of which are arranged vertically with reference 
to them. 
Dorsal with 13 or 14 rays, anal 19; 40 scales in lateral line, 9 in a cross-series, excluding the mid- 
dorsal and the mid-ventral rows. 
- Variation in number and disposition of photophores is confined to the anal series. The total num- 
ber of these varies from 13 to 15 (abnormally 12 in the anterior group on one side of one specimen), 
the prevailing number being 14 (7 + 7). The following combinations occur: 7 + 7 and 7 + 7 in 26 speci- 
mens; 7+ 7 and 7 + 6 in 3; 7 + 7 and 6 + 7 in 1; 7 + 7 and 7 + 5 in 1; 7 + 6 and 7 + 6 in 6; 7 + 8 
and 7 + 8 in 1; 7 + 8 and 7 + 7 in 1; 7 + 8 and 8 + 7 in 1; 7 + 8 and 6 + 7 in 1; 8 + 6 and 8 + 6 in 5; 
8 + 6 and 8 + 7 in 2; 8 + 7 and 8 + 7 in 1. From this it appears that the predominating combinations 
are 7 + 7, 7 + 6, and 8 + 6, In the anterior group, 8 occurs in 17 cases, 7 in 79, and 6 in 2; in the 
posterior group, 8 occurs in 5 cases, 7 in 65, 6 in 27, and 5 in 1. Thus, while 7 is the prevailing 
number in each group, the anterior group varies most frequently toward 8, the posterior group in the 
