596 BULLETIN OF THE TTNTTED STATES FISH COMMISSION. 



Myctophum fibulatum (liillicrt & Cramer. 



Two gperimens, dredficd at depths nf 2:i0 tn 2S4 fatlidiiif', (1(.) not differ from tlie type in number 

 and distriliution of the pliotoplioref. The species is peniliar in liaving but 3 eipiull}- spaced pairs 

 of ventral iiliotophores alonj; median line, the second pair lieintr disiiUieed laterally, almost vertically 

 above tlu' first pair. The anterior pair of the supra-anals lies over the interspace between the third 

 and fiiui'th vcntrals. A small black-ringed |)hotophore on the anterior orbital rim escaped notice in 

 tl]e type. One small sjH'cimen was taken in the surface tow-net, at station .'W89, north of Molokai; 

 others were obtained at stations 3899,. Pailolo Channel, 283 to 284 fathoms, and 4082, off tlie north 

 coast of Maui, 220 to 238 fathoms. 



Myetophuiii 0Htliiliim liilbfrt * rraincr, Proc. U. s. N'lit. Mvis., xix. Is'.iT. 411. |il. 3S, fig. 2 (not Hk. S. as erronefiusly imli- 

 cMlert on plate 3S and in tin- drscriptiiai i, 



Myctophum marg'aritatuin, new s|)<'ci<'s. Plate 68, Fig. 2. 



Tyiie 80 mm. long, from the surface at station .3930, off the south coast of Molokai; type. No. 

 51536, U. S. Nat. Mus. 



Closely related to .1/. nffiiif Liitken and ^f. OjiaUmnn Goode & Bean, from the Atlantic. These 

 two species are insufficiently de.scribed, and may even prove to be identical with each other and with 

 tlie species here described. Certain ilifferences are, however, in<licated in the descriptions as they 

 stand. 



(ireatest depth of body 24 hundredths of total length without caudal; least depth of caudal 

 peduncle 8; length of heail 27; diameter of orbit 9; interorbital width 10; length of snout 4; length of 

 maxillai'y 17: distance from ti]i of snout to front of dorsal 44, from front of dorsal to adipose dorsal 37, 

 from front of adipose dorsal to rudimentary caudal rays 21, from tip of snout to ventrals 41, from tip 

 of snout to origin of anal 57; base of anal 27; length of pectoral 15; length of ventral 12. D. 13; A. 20; 

 P. 15; \^. 9, the outermost ray minute; .scales in the lateral line 40, the 41st on the base of the caudal 

 tin and without tube; 9 scales in a cross-series excluding median rows on back and belly. 



Body rather slender, heavy forward, snout very short and bluntly rounded, the profile descending 

 in a strong, nearly uniform curve from occijiut to front of nostrils; eyes very large, one-third length of 

 head, slightly less than frontal width above their middle; snout and frontal region with low concealed 

 median crests; mouth oblicjue, maxillary gradually w lening posteriorly, extending well Ijehind the 

 orbit, its lengtli slightly less than two-thirds that of head; teeth mimite, in narrow bands in each jaw, 

 those on vomer in 2 small, widely .separated clusters, those on palatines larger than the others, in single 

 series; in addition to these, all the roof of the mouth, excej)! its middle line, is covered with minute 

 asperities; preopercle nearly vertical, its margin entire; opercle entire and unstriated, exce]it tor a 

 short space below the upper posterior angle, where the margin is weakly rihlicd and toothed; gill- 

 rakers long and slender, 5-|-l'i on outer an-li, the longest slightly more than half the diameter of orljit. 



First dorsal ray over the eleventh scale of lateral line; root of ventrals ojjposite the ninth ortenth; 

 first anal ray under the eigliteenth, last under the thirty-first ; origin of adipose dorsal over the twenty- 

 ninth; pectorals not reaching middle of ventrals; ventrals not reaching vent. 



Scales all thin, not si>inous, the margins entire or only gently notched or sinuate, tho.se of the 

 lateral line not enlarged. 



Photo|iliores arrangeil as in .1/. ajline Gunther and M. (i/uiHiiiini Goode & Bean; preoculars 1, 

 minute, similar to those on body, on the lower anterior orbital rim; mandibulars 3; operculars 2, 

 the one behind the tip of maxillary concealed beneath the margin of the preopercle; pectorals 3, 

 forming a right angled triangle, the middle spot on lower edge of pectoral base, the ujjper encroaching 

 on third scale of lateral line, the lower on line between pectoral base and the first thoracic spot; 

 thoracics 5, the third and fourth less widely separated than the others, the 5 jiairs arrangeil in 2 nearly 

 siraiglit gently diverging lines; supra-ventrals 1, nearly midway between the axil of the ventrals and 

 the lateral line; ventrals 4, ei|ually spaced; supra-anals 3, in an oblicjne line directed toward interspace 

 between third and fourth ventrals; anals 13 to 17 (usually 14 or 15), in 2 well-separated groups, 

 8-10+5-7, the usual fcjrinula being 9+6, 9+5, or 10+5, the series throughout parallel with the lower 

 outline; posterolateral 1, over the last antero-anal; caudals 2, closely approximated, the posterior little 

 higher than the anterior; the third supra-anals and the ])osterolaterals encroach upon the series of 

 scales which bear the lateral line, the former below the eighteenth, the latter below the twenty-eighth 



