FISHES OK HAWAIIAN ISLANDS. 639 



Peristedion engyceros (< aiiithcr). 



Tliis s])eci(^« hil-s been kiiuwii hitherto imly from tlif type, which (■(Jii.-iisti'il of fratrnu'iits of a (h-ied 

 spci-iiiien sent from the Hawaiian Isrlands to tlie Britisli Museum. The investigations of the A/hutrons 

 liav(^ now shown it to he. abundant aliout the islands on sandy l>ottom at depths of I'tO to 250 fathoms, 

 about 60 sjiecimens beinj; secured at 17 stations. The following description is ba.sed upon this 

 material. 



Length of head, measured from front of jirema-\illarics to op<'ivular margin, L'.T) iu li'Ugth from 

 front of premaxillaries to ha.se of caudal; dei>tli 5.7"); greatest width of liead ;!.i)5. 1 >. \ n, I'O (rarely 

 21); A. 20; K 14 i 2. 



The species differs strikingly from /'. //»;».•< in the shape of the rostral processes, which are very 

 slender, parallel, of nearly equal width throughout; tlie distance between them equals their length, and 

 is about half length of snout without them; width of the snout opposite anterior nostril equal to 

 its length; interorhital space dee])ly concave, with a median groove, which widens posteriorly; a small 

 postocular spine, a much stronger sjiine at enil of oecijiital ridges, and small spines at end of jjaroccipital 

 opercular crests; ujijier orbital rim spinulose along its entire length; in the young are usually 2 preor- 

 hital spines which disappear iu adults;, behind snout, the lateral margins of head are expanded to form 

 a thin knife-edge, which leads to the long preo]iercular spine: the anterior limit of the expanded e<lge 

 markeil by a projecting spine, to the base of which runs a vertical ridge from front of eye and an ol)lic|ue 

 ridge from middle of lower orbital margin; all the plates of the head minutely prickly; on median por- 

 tion of snout 6 or S stronger hooked spines, distril)uted on the rostral ridges; interorl)ital width 0.(i5 

 diameter of eye, which is contained 4.4 times in head; i)remaxillaries protruding beyond mandible fora 

 distance equal to 0.2 length of head; length of maxillary contained 2.S times in head, and equal to the 

 greatest external width at angles of mouth; the large barbel, when laid back, extending to base of ven- 

 tral fins; along its anterior margin it bears a series of smaller barbels, mo.stly arranged in pairs; seven 

 barbels, similar to these smaller ones, occurring on each side of symi)hy,sis, on lower lip and adjacent 

 p(.>rtions of mandible; the most posterior of these, on the mandible, is always jiaired; mouth toothless; 

 gill-rakers 5 -f- Hi or 17, the terminal ones represented by papilhe; spinous dorsal joined to soft dorsal 

 at extreme base; pectorals long, reaching fifteenth plate along lateral line, length c)f ujijier rav equaling 

 distance from tip of snout to front of pupil; upper free ray contained 2.25 times in head. 



Dorsal series of plates with strong backwardly-hooked spines which decrea.se in size posteriorly, 

 almost di.sappearing on caudal peduncle; behind these 2 movable sjjines along base of upper caudal 

 lobe; the upper lateral series of plates accompanies the lateral line, which opens externally in 3 pores 

 for each plate, 1 above and 2 below the s]jine; behind the sliort anterior arch thi? spines are strong; 9 to 

 12 spines in front of nuddle of caudal peduncle bear at the l)ase of the anterior side a short, strong, 

 straight spine, directed obliquely forward; spines of ventnd row of plates obsolescent, perceptible to 

 the touch, but scarcely visilile along course of anal tin; only 2 or ;> of the anterior plates of the series 

 have well-developed spines. Dorsal series containing 29 or 30 plates, including 2 on liase of caudal; 34 

 or 35 in upper lateral, 23 or. 24 in lower lateral series, and 2f) or 27 in ventral series, including 2 on ba.«e 

 of caudal. 



A specimen in life was pink, witii a yellowish tinge, the tips of rostral proces.ses, the fins and long 

 barbels deeper pink or almost scarlet, the tips of fins and ends of l)arl)els wliite; breast and belly wliite; 

 upper parts of head and body marked with fine olive dots and lines, those on head arranged regidarly 

 anil symmetrically; some specimens ajipear nearly or wholly plain, without spots and lines; pectorals 

 whitisli, streaked or spotted with olive; anal marked with 3 indistinct narrow yellowisli vertical ))ars; 

 other fins unmarked. 



Thes])ecies was taken at the following stations: .Nos. .3919, off the south coast of Oahu, 220 to 257 

 fathoms; 3920, off the south coast of Oahu, 2(i5 to 2S0 fathoms; 393S, vicinity of Laysan, 148 to 103 

 fathoms; 3941, vicinity of Laysan, 70 to 110 fathoms; 3957, vicinity of Laysan, 173 to 220 fatlionis: 

 3986, vicinity of Kauai, 55 to 362 fathoms; 3993, vicinity of Kauai, 201 to 218 fathoms; 4017, vicinity of 

 Kauai, 305 to ? fathoms; 4079, off the north coast of Maui, 143 to 178 fathoms; 4080, off the north coast 

 of Maui, 178 to 202 fathoms; 4081, off the north coast of Maui, 202 to 220 fathoms; 4082, off the north 

 coast of Maui, 220 to 238 fatlioms; 4083, off the north coast of Maui, 238 to 253 fatiioms; 4115, off tlie 

 west coast of Oahu, 195 to 241 fathoms; 4116, off the west coast of Oahu, 241 to 282 fathoms; 4117, off 

 the west coast of Oahu, 253 to 282 fathoms; 4132, vicinity of Kauai, 257 to 312 fathoms. 

 Pcristellmsaigyccros Qiinthet, Proc. Zool. .Soc. Lmui. 1S71, 663; Giintlier, Fischc der Sudsec, 168 (tei-\ tigure). 



F. c. H. I'liK, I>i. 2—5 



