580 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Color black; lower side of head and fins abruptly pale; a row of photophores from isthmus to base 
of pectoral; a double row from between lower pectoral rays along each side of body just above base of 
anal and along lower side of caudal peduncle to base of caudal fin; a row from behind pectoral base to 
ventral; two on side above end of ventral; two above anal; two behind shoulder girdle above pectoral; 
one below eye. 
This species has the anal fin more advanced than any other referred to Gonostoma or to Cyclothone. 
This trait may be regarded as of generic value. As it appears also, although to a less degree, in 
Cyclothone bathyphila, the type of the nominal genus Neostoma of Vaillant, we may provisionally adopt 
the genus Neostoma for these two species, which have the anal inserted well in front of the dorsal. 
MYCTOPHIDdJ. 
10. Neoscopelus alcocki Jordan & Starks, new species. (PI. 2, figs. 1 and 2.) 
One specimen, 19 cm. long, from station 3709, in Suruga Bay, in 173 to 260 fathoms; type, No. 
51477, U. S. Nat. Mus. 
Head 3 in length; depth 4; D. 13; A. 12; scales 4-33-4 ; eye 5 in head; snout 3.5; maxillary 2. 
Body rather robust, subfusiform, head rather pointed in profile, broad and somewhat depressed 
above; mouth large, oblique, maxillary extending to below posterior margin of orbit, not dilated 
behind, posterior border truncate; teeth small, in villiform bands; eye moderate, cheek hroad, not 
oblique in position; scales large, entire, firm, roughened on the surface, nearly all fallen in specimen 
examined; lateral line well developed; luminous spots, large, in about 6 rows on breast, about 14 in a 
lengthwise series from isthmus to ventrals, then a median and two lateral rows, to opposite front of 
anal, 10 spots in outer row, the posterior one smaller; an oblong circle of 10 small photophores about 
the vent; a row of 15 small photophores, continuous with inner lateral row before vent, from opposite 
vent to base of caudal, most of the median members of this series double; there is also an inner series 
of minute white dots along base of anal rays; a median row of small photophores behind anal below 
caudal peduncle. Dorsal rather large, inserted before ventral, its longest rays about half head; longest 
anal ray 2.4 in head; caudal well forked; pectoral long, 1.1 in head; ventral long, 1.75; gillrakers long 
and slender, 3 -(-12 in number. 
Color pale or brownish above, belly black; a dusky shade at base of caudal and pectoral; inside of 
mouth black; luminous spots pale, with a dark ring. 
This species is very close to Neoscopelus macrolepidotus of the Atlantic. The sole important differ- 
ence apparently is in the arrangement of the photophores on the posterior part of the body. In the 
figures (Nos. 108 and 109) given by Goode & Bean, the arrangement is quite unlike that seen in the 
Japanese fish. In the plate, the two lateral rows of spots found on the abdomen are represented as 
continuous to the base of caudal. In the Japanese fish the outer row is not continued behind the 
front of anal. The inner lateral series is continued, the spots becoming smaller. There is a ring of 
little spots about the vent, and a series of little dots along base of anal. 
The species abundant about Hawaii, called Neoscopelus macrolepidotus by Gilbert & Cramer, seems 
to be the same as the Japanese fish. 
1 1. Diaphus watasei Jordan & Starks, new species. 
Head 3.8 in length; depth 5.2; eye 4 in head; snout 5.5; maxillary 1.4; D. ii, 13; A. ii, 13; scales 36. 
Body moderately elongate and compressed, more slender than in Diaphus (jEthoprora) effulgens, 
the nearest related species, head more pointed; eye small; snout very short, truncate at tip; cheeks 
very oblique; scales caducous, all fallen in type; those along lateral line preserved in one specimen, 
and considerably enlarged; a lunate luminous gland in front of eye, extending backward to a point 
a little behind front of pupil; a short luminous tract above this; all these coalescent over snout in a 
large pale area like the headlight of an engine, the front part distinctly paler than that, before the eye; 
luminous spots distinct, 4 + 4 + 1 -j- 4 + 4 + 6 + 1 +5 + 4; the last 4 in a curved row at base of caudal, 
5 before this, then 1 posterolateral spot before which are 6 in a curved row continuous with it; then 
4 mediolateral spots in a V-shaped series, 4 more, 1 of them out of line, then a single spot above base 
of ventral; 4 spots before ventral and 4 before pectoral. One single spot shows the characteristic 
division, or theta-form (6), which suggested the name Diaphus. It is probable that, in life more spots 
had this form, and that there is no real difference between yEthoprora and Diaphus. Dorsal fin high, 
its last ray about over first of anal, its longest ray 1.2 in head; anal tin moderate; pectoral short and 
broken, about 3 in head; ventrals 1.6 in head; caudal broken. 
