FISHES OF HAWAIIAN ISLANDS. 
69 
between Australia and New Zealand. They are near R. andrex Liitken, from which they seem to 
differ in the blunter snout, tbe more slender tail, and in having the postero-lateral photophore some- 
what before the adipose fin. 
Type, No. 50622, U. S. N. M. (field No. 05805), 1.3 inches long, collected by tbe Albatross at 8 
p. m., September 8, 1899, at the surface at 137° 35 / W., 10° 57' N. ; cotype, No. 2736, U. S. F. C., same 
size, collected at same time and place. 
Ithinoscopelus oceanicus Jordan & Evermann, Bull. U. S. Fish Comm., XXII, 1902 (Apr. 11, 1903), 1G8, near Hawaiian Islands. 
Genus 31. CENTROBRANCHUS Fowler. 
This genus is close to Rhinoscopelus, from which it seems to differ in the character of the gillrakers, 
which are short sparse clusters of asperities on the first arch. Two species known, both from Hawaiian 
waters. (See Section II.) 
Centrobranchus Fowler, Proc. Ac. Nat. Sei. Phila. 1903 (Jan. 13, 1904), 754 (choerocephalus) . 
28. Centrobranchus choerocephalus Fowler. 
This species, fully described in Section II of this work, was based by Mr. Fowler on 4 specimens 
in the Museum of the Philadelphia Academy, which were originally identified by Mr. Fowler with 
Rhinoscopelus coruscans (Richardson) , and later thought by us to be identical with the specimen which 
we described as R. oceanicus. Upon a reexamination of his specimens Mr. Fowler finds them to 
represent a distinct genus as indicated above. 
Centrobranchus choerocephalus Fowler, Proe. Ac. Nat. Sci. Phila. 1903 (Nov.), 754, near Sandwich Islands. (Type, No. 7972, 
Ac. Nat. Sci. Phila. Coll. Dr. Wm. H. Jones.) 
Ithinoscopelus oceanicus Jordan & Evermann, Bull. U. S. Fish Comm., XXII, 1902 (Apr. 11, 1903), 108 (only the reference 
to Dr. Jones’s specimens). 
Genus 32. MYCTOPHUM Rafinesque. 
Body oblong, compressed, covered with cycloid scales, those in the lateral line not much enlarged; 
caudal peduncle rather slender; head short, compressed, with limb of preopercle nearly vertical; 
mouth large; jaws about equal; premaxillaries long and slender; maxillaries well developed; snout 
more or less blunt and declivous; teeth in villiform bands on jaws, palatines, pterygoids, and tongue; 
eye large, gillrakers long and slender; air-bladder small; dorsal fin entirely in front of anal, overlap- 
ping it little or not at all; ventrals 8-rayed, under or but slightly in front of first dorsal rays; pectorals 
well developed; soft dorsal slender; precaudal photophores 2; supraanals in 2 groups, with 1 or 2 pos- 
tero-laterals above the interval between them. Species rather numerous, widely distributed, 4 known 
from Hawaiian waters, and described in Section II. 
Myctophum Rafinesque, Indice d'lttiologia Siciliana, 56, 1810 (punctatum). 
Scopelus Cuvier, Regne Animal, Ed. II, 169, 1817 (humboldti). 
Nyctophus Cocco, Giorn. Sicil., 44, 1829 (amended orthography of Myctophum). 
Genus 33. DASYSCOPELUS Gunther. 
Dorsal and anal fins touching the same vertical, but not overlapping; scales hard, persistent, ctenoid, 
those of lateral line much enlarged; anal terminating below adipose dorsal; body elevated, somewhat 
compressed; caudal peduncle rather slender; luminous scales on the backof caudal peduncle; arrange- 
ment of photophores much as in Myctophum. Species few, remarkable for the firm, rough scales. 
Two species known from the Hawaiian Islands (D. spinosus and D. pristilepis) described in Section II. 
Dasyscopelus Gunther, Cat., V, 405, 1864 ( asper ). 
Genus 34. NEOSCOPELUS Johnson. 
Body oblong, compressed; mouth-cleft not extending beyond eye, the upper borders formed 
entirely of the premaxillary; the maxillary dilated below and furnished with a small supplementary 
piece; scombinate bands of teeth in both jaws, on palatine bones, and on vomer, also scombinate 
