DISCUSSION OF SPECIES AND THEIR DIS'l'KlIirTION. 400 



leno-th ofliead; V.ll; T. 13; liciglit 7 in total; licad 0. Interorhital area 2i in head. (M|iial 

 to eye. Snout 42 iu bead. Teeth iu villifoiin bands. ( ullmkeis very short, ndnute, about 

 18 below the aiiijle. No pseudobvancliia'. iJaibel I'i in eye. 



The type, number 37;{37, is a young .speeimen, 102 millimeters lon.u, obfained by the 

 Albatross at station 2398, N. Lit. 2So 45', W. long. SO'' 20', at a dei)th of 227 fathoms. 



LIONURUS, Gunther. 

 Lioniiriis (as 8ul)gemis), GiiNTHER, Challeiigor Rcjxirt, xxii, 121. 



A genus resemblint;- .Vrte»v/c».>(, but with indiricated, smooth, and (hiecid scales; soft, 

 cavernous bones; small eye; filamentous ventral ray; minute l>arbel, and i)roJecting, pointed 

 suoiit. A eharaeteristic bathybial ty])e. 



Giinther's Macnints micruh'2>is, [loc. cit.) from oti' iMatuku, Fiji Islands, 315 fathoms, is 

 provisionally referred by liiiu to this division, though based ujion immature specimens. 



Lionurus liolejjis, Gilhcvt (Proe. U. S. Nat. Mus., xiii, 1890, 117), was taken l)y the 

 Albntross, off the coast of California, in 093 fatlioms. 



LIONURUS FILICAUDA. Giinthek. (Fi<;nro :M2.) 



Corypliannides (Lionurun) filicaiida, (ifNTDEK, Ann. and Mag. Nat. Hist., 1S7S; Chulk'iigi-T Krport, x.xii, L'7, 

 pi. xxxiv, fig. B. 



Snout considerably projecting beyond the mouth, pointed in the middle; it is twice as 

 long as the eye, which is unusually small, only half as wide as the interorbital space. 

 Mouth rather wide, extending beyond the center of the eye. Upper teeth villiforni, in a 

 very narrow band, those of the mandible very small, biserial. I'.arbel minute. Pra'Oper- 

 culnm with the angle jirodnced backwards, broadly rounded and crenulated on the margin. 

 The terminal portion of the tail is prolonged into a long filament, more slender than in 

 any of the other si)ecies. Bones of the head soft. 



Scales of moderate size, thin, cycloid, and deciduous; six or seven in a transverse 

 series between the first dorsal spine and the lateral line; snout and iiderior half of the 

 infraorljital region naked. The second dorsal spine slender, with the barbs iu front veiy 

 inc'onspicuous and sometimes entirely absent. The distance between the two dorsal fins is 

 less than the length of the head. The outer ventral ray produced into a short filament. 

 Distance between vent and isthmus less than the length of the head. 



Head and trunk whitish, tail brownish, lower part of the head and gill-opening black. 

 {Gunihvr.) 



Eadial formula: D. 11; J'. 20; V. 9; Ca^c. ])yl. 7. 



The GlmUeiKjei- obtained this species from the Antarctic Ocean and from the deej) sea 

 on both sides of the Scmth American Continent: from station .•'.2;-), at a depth of 2,050 

 fathoms; from station 323, at a depth of 1,900 fathoms; from station 299, at a dei)th of 2,100 

 fathoms; from station 15S, at a deptli of 1,800 fathoms; from station 157, at a depth of 1,950 

 fathoms, ami from station 140, at a depth of 1,375 fathoms. 



Dr. Giinthcr holds that this species is clearly oue of those of the family wlii(-li extend to 

 the greatest depths, since the small eye, the soft bones, the lack of firmness in the scales, 

 and the tilameutous tail indicate its abyssal abode. 



TRACHONURUS, Gunther. 

 TrKclioiiiinis (as subgeuns), fti'NTHEH. Cliallcngfi' Rejiort. xxii, 1887, 121. 



A genus resembling MHOurxs in fiain and dentition, but with incomplete st|uamation, 

 the skin being densely studded with erect spines, strongest at the bases of the vertical 

 fins, space between the vent and ventral scalelcss; .snout short, compressed; intenubital 

 ridge ob.solete; mouth small, lateral. 



In addition to the type species, .1/. rinosiis, Giinther (Challenger Kep<>''<? >^^"' 142, pi. 

 xxxvi, fig. 1!) from Japan, 345 fathoms, and the Philii>piues, 500 fathoms, our Mulacocepludm 

 sulcatus appears to belong to this group. 



