414 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



(e) Tho head is densely covered with small spinous scales or prickles, especially 

 numerous on top of head and on opercles. In 1. cana^iculatua the head is either naked 

 or sparsely covered, and tlie opercles are almost or quite naked. 



(/) Three pairs of slender lilameuts on top of head, the anterior pair the largest, 

 placed above back of orbit; the second i)air is in front of and slightly within the 

 occii)ital ridges, the third pair on occipital spines. An additional i)air on opercles 

 seems to be less constant. The supraocular pair alone is present in /. canaliculatus. 



{g) The mucous canals and pores, though large, are less developed than in /. eana- 

 UcnlatuH, the fish having in general the bathybial characteristics less pronounced. 



The agreement with /. euryops is closer than Avith /. canaliculatus. In fact it seems 

 to diifer from I. euryops only in the much smaller eye and somewhat wider inter- 

 orbital space, agreeing w'ith /. euryops in all those respects in which it difters from 

 /. canaliculatus. In 7. lyicinalis the eye is 2§ to 3 in head, and but 11 times length of 

 snout, and the least iuterorbital Avidth is 11 or 12 times in head. In I. euryops (co-type 

 No. 45367, U. S. Nat. Mus.) the eye is 21 times in head and twice the length of the 

 snout, and the least iuterorbital Avidth 16 times in head. It does not seem probable 

 that the species Avill vary to that extent. 



Dorsal ix-21 to 23; anal 18; pectoral 18; caudal 9. Head 3y to 3i in length; 

 depth 5|. Maxillary leathing middle of pupil, 2^ in head. Upper preopercular 

 spine slender, forked at tip, directed upward and backward; the second and third 

 spines simple, slender, directed downward and backward, the fourth downward 

 and forward. Iuterorbital space shallowly grooved, the groove widening back- 

 ward into an occipital depression bounded iu front by the somewhat elevated 

 interocular space, laterally by the occipital ridges. The supraorbital rim is eleA'ated 

 in front and behind. The occipital ridges are low, broad, and rounded anteriorly, 

 becoming narrower and more crest-like posteriorly. In addition to the prickles and 

 plates already mentioned, there is a band of spinous scales behind axil of pectorals. 



Spinous dorsal low, the longest spine 2A in head, the longest ray of soft dorsal 2 

 in head. Pectorals reaching beginning of horizontal portion of lateral line, the 

 lower rays thickened, their membranes incised. Veutrals short, scarcely reaching 

 vent. Anal papilla large. 



Color in si)irit8 : Light-brown above, with four blackish crossbars, one under 

 spinous dorsal joining the dark axillary patch, tAvo under soft dorsal, and one at base 

 of tail merging into the uniform deep brown of the under parts. Head, light brown 

 above and below; subocular ring dark brown, this streak widening forward and 

 crossing upper and lower lips. A small brown patch at base of exposed ])ortion of 

 maxillary. Opercle blackish. Upper half of pectorals light, with or Avitliout a 

 brown basal bar, the distal portion indistinctly barred with light brown. Lower 

 half of pectorals and all of A'entrals dark brown or black. Dorsals blackish, darkest 

 above cross))ar8 on back. Anal black. Caudal whitish, dusky aboA^e toAvard tip. 



Numerous specimens 50 to 110 mm. long, from stations 3324, 3330, 3331, and 3332, 

 Bristol Bay, Alaska, at depths of 109, 351, 350, and 406 fathoms, respectiA'ely. 



Tho following notes are drawn from one of the co-types (No. 45367, U. S. N. M.) of 

 /, euryops, kindly loaned to us for that purpose by Dr. Bean. 



Specimen 77 mm. long, 65 mm. to base of caudal fin. Head 22 mm. to end of oper- 

 cular spine; depth 11; orbit 10^; snout SJ; maxillary 11; iuterorbital width lj\. 



Dorsal ix-23; anal 19; pectoral 18; caudal 9. Preojtercular spines as in /. vioi- 

 nalis, the upper spine abnormal on one side, showing three points instead of tAvo. 

 BeloAV the forked spine are three others — one directed backward and a little down- 

 ward, one nearly vertically downward, and one doAvnward and forward. Nasal spines 

 strong. Occipital ridges obvious, Avith easily perceiitible slender spines about as in 

 I. ricinaUs, the ridges broadly rounded anteriorly, scarcely ridge-like until imme- 

 diately in front of spines. Head r.ither closely invested Avith scales, scarcely so 

 rough or so numerous as in I. vicinalis, but more so than m /. canaliculatus. Opercle 

 covered Avith scales. Filaments as in I. vicinalis — one pair above eyes, one ante- 



