110 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



ence in the region. There is no doubt that the species is distinct from Echiostoma bar- 

 but inn, as it has very small subequal teeth: 



OPOSTOMIAS, Gunther. 



Echiostoma, sp., Gun'THei:, Ann. and Mag. Nat. Hist., n, 1878, 180; Narrative of Challenger Expedition, I, 412. 

 Opostomias, Gt'NTHER, Challenger Report, XXII, 238 (type, 0. micripiuis, GCNTHER, loc. cit., 208, pi. mi, 

 fig. A). 



A genus of stomiatoid fishes, closely allied to Echiostoma, but differing in dentition, 

 the jaws aimed with few strong, nondepressible teeth, received in deep hollows in the oppo- 

 site jaws. Maxillaries and palatines toothless. Pectoral with separate ray. Body naked. 

 An immense number of luminous organs. 



This genus is known from a single specimen, loi inches long, captured by the Challen- 

 ger south of Australia, at a depth of 2,150 fathoms, described by Gunther as Echiostoma 

 micrijmtis. (Fig. 132.) 



5RAMMATOSTOMIAS, Goode and Bean, n. g. 



Similar in general appearance to Echiostoma. Head short, compressed. Body com- 

 pressed, moderately elongate. Dorsal and anal with numerous rays, placed opposite each 

 other and close to the root of the caudal. Ventrals in advance of the middle of the body, 

 at a great distance from the vent. Pectorals placed near the abdominal outline, consisting 

 of a short filament very slightly separated from the rest of the fin, and several rays con- 

 nected by a membrane. Two rows of minute phosphorescent spots on the body similar to 

 those in Echiostoma. A very long and slender hyoid barbel. Mandibular teeth very 

 unequal in size, comparatively few in number, arranged in two rows, an outer row of fixed 

 teeth and an inner row of depressible ones. The first pair, near the tip of the mandible, is 

 very greatly enlarged and passes outside of the upper jaw when the mouth is closed. Inter- 

 maxillary teeth uniserial or nearly so, the edge of the bone posteriorly with minute cirri. 

 A pair of small, fixed, curved fangs in front, followed by a pair of larger movable ones. 

 Vomer toothless. Palatines with several weak teeth. No lingual teeth. Upper pharyn- 

 gals present. A pearl-colored spot on the cheek, similar to that in Echiostoma. Four 

 gills; a short, narrow slit behind the fourth. Gill rakers not numerous, short, spine-like. 

 Gill lamina 1 increase in size backwards. A series of pigment cells along the median line of 

 the body, so arranged as to simulate a lateral line. Eye small, Caudal lobes apparently 

 unequal. Skin naked, its whole surface sprinkled with minute raised pigment spots, each 

 with a light center. 



GRAMMATOSTOMIAS DENTATUS, Goode and Bean, n. s. (Figure 133.) 



The greatest height of the body equals the length of the head without the snout and is 

 one-seventh of the total length without caudal. The maxilla is long and slender; its length 

 is contained 6£ times in the total. The length of the mandible is contained 5| times in the 

 total. The eye is as long as the snout, about one-fifth as long as the head. The nostrils 

 are a little nearer to the eye than to the tip of the snout. The anterior nostril is placed 

 nearly in front of the middle of the eye in a very short tube ; the posterior is on a level with 

 the top of the eye and is merely a small slit. The supramaxillary and intermaxillary are 

 closely welded, but their separation is marked by a changing in the character of the teeth; 

 those on the supramaxillary being minute cirri. The large fangs in the tip of the mandible 

 are two-sevenths of the length of the upper jaw. 



The hyoid barbel is placed at a distance from the symphysis of the mandible, which is 

 about equal to the enlarged fangs of the mandible, or one-fifth of the length of the mandi- 

 ble. The length of the barbel is nearly one-third of the total. The pectoral is situated close 

 behind the head and near the ventral outline; its first ray is distinct from the other three, 

 although placed close to them, and is not produced. The greatest length of the pectoral is 

 about one-fourth that of the head. The ventrals are placed in advance of tin 1 middle of 

 the total length, their distance from the origin of the pectorals being one-half as great as 



