NO. 2149. JAPANESE MACROUROID FISHES— GILBERT AND HUBBS. 139 



ings; the small elongate scales at right angle, as in Anguilla and Oto- 

 phidium; and in the increased number of pectoral actinosts. We do 

 not accept Regan's reference ^ of Melanonus ^ to this family, since 

 Melanonus has a separate caudal fin. 



KEY TO THE SUBFAMILIES AND GENEBA. 



A\ No fold of membrane attached to first gill-arch and restricting the gill-slit; 

 gill-rakers not tubercular ; pseudobrauchiae present or absent ; second 

 dorsal ray not modified and spinelike; posterior portion of dorsal better 

 developed than posterior portion of anal. 

 B\ Two separate dorsal fins. 



C\ Vomerine teeth present ; anterior portion of anal more or less elevated ; 

 teeth in one or two series in jaws ; " neural arch of first vertebra 

 suturally united to exoccipitals and its neural spine directly and 



firmly attached to the supraoccipital crest."* Macrukoninae. 



a\ Anterior portion of anal forming a pronounced lobe; anus anterior, 

 nearly between ventrals; ventral area with striae, consisting of 

 alternating and parallel streaks of dark and silvery pigment. 



Steindachneria. 

 a". Anterior portion of anal not forming a pronounced lobe; anus pos- 

 terior, immediately before anal fin ; no ventral striae ; pectoral 



actinosts 4* Macruronus. 



C. No vomerine teeth; anal low throughout its length; teeth in bands in 

 jaws ; " the first vertebra articulating normally with the skull, its 

 neural spine not directly attached to the occipital crest." * 



Bathygadinae. 



6\ Mouth terminal ; no scaleless fossa at side of nape ; scales all cycloid, 



those along bases of dorsal and anal not modified ; gill-rakers long 



and slender; second dorsal much higher than anal; pectoral 



actinosts 3.* 



c\ Barbel vary short or absent ; teeth of moderate size— Bathygadus. 



(f. Barbel very long; teeth exceedingly minute Oadomtis. 



h". Mouth entirely inferior, the snout being greatly produced ; a scale- 

 less fossa on each side of nape ; scales rough, especially in a 

 strongly modified series along anterior portions of dorsal and 

 anal bases ; gill-rakers styliform ; second dorsal not much higher 



than anal; pectoral actinosts 6* Trachyrhynchus. 



B^ Dorsal fin single, the anterior rays more or less elevated ; head not 

 massive; a few enlarged canines in jaws; teeth present on vomer; 

 mouth terminal; scales cycloid; ventral fins not reduced; no barbel. 



Lyconinae. 

 Lyco7ins. 



iRefran, Ann. Mag. Nat. Hist., ser. 7, vol. 11, 1903, pp. 464 to 466. 



'^Melanonus gracilis GUnther, Ann. Mag. Nat. Hist., 1878, vol. 2, p. 19; Challenger 

 Reports, vol. 22, Deep-Sea Fishes, 1887, p. 83, pi. ] 4, fig. B ; Brauer, Die Tiefsee Fische, 

 1906, p. 277, pi. 12, fig. 5; Zugmayer, Res. Camp. Sci. Monaco, fasc. 35, p. 120, pi. 6, 

 fig. 1. 



Melanonosoma acuticaudatum Gilchrist, Mar. Inv. S. Africa, vol. 2, 1902. p. 106 (an 

 ally of Melanonus gracilis). 



3 Regan, Ann. Mag. Nat. Hist., ser. 7, vol. 11, 1903, p. 465. 



* Regan (Ann. Mag. Nat. Hist., vol. 11, 1903, p. 462) gives the number of actinosts iu 

 thi.s family as follows : Bathygadus and Oadomus, 3 ; Macruronus, 4 ; Hymenocephalus, 5 ; 

 Macrurus, Coruphaenoides, and Trachyrhynchus, 6. We have counted 3 In Bathygadus an- 

 trodes; 4 in Hymenocephalus torvus, H. striatissimus, Lionurus latirostratus, and L. 

 proximusj and 5 in Coryphaenoides acrolepia and C. marginatus. 



