()()4 BTLLETIN OK THE TINITKD STATES FISH COMMISSION. 



hraiie ami siippurteil liy traiiilf jilatesaud crests. Dentition weak, fiinipose<l of minute villiform teeth 

 in very narrow bands, the latter taiiering laterally, but comprising usually at least 2 series of teeth to 

 tlicir ends; with consideralile magnification, the teeth are seen to Ix- dilated and flattened below flie 

 lip, distinctly lance-shaped; mouth terminal, very slightly overpassed by the pnjminent median point 

 of snout; inaxilhiry falling a little short of a point o[)posite hinder edge of orbit; horizontal and verti- 

 cal diameters of orbit eipial, 11.4 the length of head; ]iostericn' margin of preopercle extending obliquely 

 upward and forward; u small opaipie lens-like body, resembling a photophore, occupies the middle 

 of the breast, and is conm^cted by a raiseil blac-k line below the peritoneum with a similar body 

 immediately before the vent. 



Scales verj- thin and deciiluous, many of them smooth and unarmed, as described in tlie tyj>e. 

 ( Xhers may have a few ( 1 to 10) short, scattered spines, wholly without detinite arrangement. 



In specimens taken July 21 at station 40.SS, the eggs have nearly reached maturity, the ovaries 

 exceeding in size all other contents of the abdominal cavity. They are so uniform in their develop- 

 uient in some twenty specimens examined as to suggest a detinite breeding season in this species. The 

 ovaries are con][)letely uniteil in their posti'rior third, but ili verge anteriorh'. The stomach contains 

 largely digested remains of small Crustacea. There are liut few (about 12) pyloric cteca. 



The iH'culiar and highly develojied color-]iattern of the gular membrane, sides of throat and area 

 on outer side of base of veiitrals has been pointed out in the original description of the siiecies. In 

 addition to the conspicuous dark line along middle of side of tail, there is a hand of dark s]iecks above 

 this line, separated from the base of anterior part of dorsal fin by a colorless streak; below the middle 

 of tail is a wide colorless band, then a narrow streak composed of black specks, separated from base of 

 anal by a narrow colorless streak; posterii.irly, all the dark streaks blend, the terminal p(jrtion of tail 

 being distinctly blackish; tip of snout marked by a narrow black transverse line, often interrupted; 

 lining of Tuouth largely colorless; the bands of teeth black; a transverse black arch overlying palatines 

 and head of vomer, and a black streak on tlfior of njontli in front of tip of tongue; linings of shoulder 

 girdle and brancliiostegals black. 



There can be no doubt of tlie close relationship between the 2 Hawaiian species of Ilijiiii'noi'rplialnx 

 and the Atlantic 11. iUtUcitx (liglioli, the type of the genus. They agree not only as regards the smooth 

 dorsal spine and the large terminal mouth with narrow bands of minute equal teeth, but in the 

 presence of the jjcculiar coloration above liase of ventral fin, and the small tubercle on the median line 

 of breast. In 11. Italinis, the last-mentioned characters are described by Collett (Poissons de I'Hiron- 

 delle, l.HVIti, p. 87), in the following terms: " Imniediatement au-dessus des ventrales, la peau du ventre 

 est legcrement rayee, du moins <-hez les jennes individus; ces raies ilescendent vers la ligne ventrale. 

 En avant des ventrales, on reniarque snr la ligne niediane du corps une petite protuberance mamillaire 

 ronde." The o species agree also in their very small size, the great development of the cephalic mucous 

 cavities, and the extremely caihicous scales, which show a strong tendency to lo.ss of spines. Compared 

 with JI. (7(i/ic((,s, the Hawaiian species are signalized by almost total loss of the mandibular barbel, an<l 

 by increase in number of ventral rays. Other siiecies referred to Hi/iiiriiocepli((l:iix<i seem n(jt to share 

 the common charaiiters above noted, and may with advantage, jierhajis, be removed from the group. 

 Specimens were olitained at the following stations: Nos. oSfirj, Pailolo Channel, 2o6 to 2.SI-! fathoms; 

 8883, Pailolo Channel, 277 to 284 fathoms; 3884, Pailolo Channel, 284 to 290 fathoms: .•i898, I'ailolo 

 Channel, 2.i8 to 284 fathoms; 3907, off the south coast of Oahu, 304 to 315 fathoms; 3908, off the south 

 coast of Oahu, 304 to 308 fathoms; 3909, off the south coast of Oahu, 308 to 322 fathoms; 3910, off the 

 south coast of Oahu, 311 to 337 fathoms; 3911, off the south coast of Oahu. 334 to 337 fathoms; 3912, 

 off the south coast of ( laliu, :;10 to 334 fathoms; 3914, off the south coast of Oahu, 289 to 292 fathoms; 

 3915, off the south coast of Oahu, 299 to 330 fathoms; 3917, off the south coast of Oahu, 294 to 3;!0 

 fathoms; 3918, off the soutli coast of Oahu, 2."i7 to 294 fathoms; 3925, off the south coa.st of Oahu, 299 

 to 323 fathoms; 4021, vicinity of Kauai, 280 to 399 fathoms; 4025, vicinity of Kauai, 275 to .308 fathoms; 

 4085, off the north coast of Maui, 207 to 283 fathoms; 40S6, off the north coast of IMaui, 283 to 308 

 fathoms; 4087, Pailolo Channel, 300 to 308 fathoms; 4088, Pailolo Channel, 297 to 300 fathoms; 4089, 

 Pailolo Channel, 297 to 304 fathoms; 4090, Pailolo Channel, 304 to 308 fathoms; 4091, Pailolo Channel, 

 .300 to 308 fathoms; 4105, Pailolo Channel, 314 to 335 fathoms; 410(;, Pailolo Cliannel, 335 to 350 

 fathoms; 4140, Pailolo Channel, 3:>9 to 437 fathoms. 

 Ilijmi uitaphalus atili-riis (iill«Tl A Cnniu'r. Priic. U. S. Nat. Mas., XIX, 1897, 4'JS, pi. m.vi. IIk. 2. 



a Tlie above was written before tbc description of //. MriaUssiniua, H. papyraccua, aiul H. Icthonaims from .lapan (see 

 Jordan & Gilbert, Bull. V. S. F. C for 1902. pp. fiP-MIII'.), all of which possess the above-mentioned characters of the genus. 



