DISCI SSION OP SPECIES AND THEIR DISTRIBUTION. 41 



B. Anal inserted far behind middle of dorsal. 



1. Maxillary extending to below posterior third of orbit. Scales moderate (70). Dorsal and anal 



nearly equal in length. (D. 16; A. 17. i is. microlepis 



2. Maxillary extending behind posterior margin of orbit. Scales small (ca. 105 in lat. line). 1 lorsal 



longer than anal. ( l>. II; A. 11.) B. melanocephalus 



II. I »oraal and anal nearly opposite and equal in length or Dearly so Tai.ismama 



1. Maxillary extending abonl in vertical middle of orbjt. 



a. Scales moderate (til in lat. line), (D. Hi: A. 17.) Ii. homopterus 



b. Scales rather large (about 50in lateral line), I'. 17-18; A. 17-18 B. squamosus 



1. Maxillary to vertical from anterior margin of orbit. (D.20; A. 22.) Ii. antii.i.aki m 



2. Maxillary to vertical from posterior margin of orbit. ( 1>. 22; A. 21.) B. .i:c;r.vn>i;is 



BATHYTEOCTES MACROLEPIS, GOnther. (FigureM). 

 Bathytrociea macrolepis, GOnther, Challenger Report, xxn, 225, i s *7. pi. i.\ n. Bg. b (two views of head . 



A Baihytroctes with the dorsal tin tar in advance of the anal, and the maxillary reach- 

 ing to below the posterior third of the orbit. Larue scales and short vertical tins, 'flic 

 height of the body is two-elevenths of its length; the head slightly more than one-third. 

 Head depressed, elongate, scaleless; broad across the occipital region, tapering forward; its 

 upper surface deeply concave longitudinally. Eye large; its diameter greater than the 

 length of the snout and 3^ in length of head. Interorbital space halt the diameter of the 

 eye. Suout pointed, daws equal. Cleft of mouth rather wide; the maxillary extending 

 beyond the vertical from the center of the eye. Dentition weak; teeth small, equal, pointed, 

 uniserial: intermaxillary and front of maxillary toothless; vomerine teeth in two groups; 

 palatine teeth few, about 9. 



Vent about midway between the branchial opening and the caudal. The dorsal inser- 

 tion is in advance of the vertical from the vent, and it last ray opposite the fourth ray of 

 the anal. Dorsal and anal both high in front. Pectoral lateral, its insertion opposite, the 

 lower half of the gill opening. Pectoral with broad base, extending beyond the vent to the 

 end of the anal. Its insertion is midway between the root of the pectoral and the end of 

 the anal, and directly in advance of the vertical from the insertion of the dorsal. Scales 

 small, cycloid. Lateral line straight, with wide mucous apertures. Color, uniform black. 



Radial formula: D. 15; A. 11: V. 8; L. lat. 42. 



A single specimen, 9 indies in length, in poor condition, was obtained by the Challenger 

 at station CXCVIH, north of Celebes, at a depth of LSI) fathoms. 



As the type of the genus its characters are here introduced, for purposes of comparison. 



BATHYTROCTES ROSTEATUS, GOnther. 

 Bathytrootes rosiratus, GOnther, Ann. and Mag. Nat. Hist., n, 1878, 250; Challenger Report, xxn, 1887, 227, 



pi. I. VIII. Ii". 13. 



The maxillary reaches to below the hind margin of the orbit; intermaxillary terminat 

 ing in front in a short projection. 



The height of the body is nearly one-fifth of the total length (without caudal); the 

 length of the head one-third. Hones of the head very thin and very easily ruptured, like 

 all the other parts of the body. Head compressed, moderately deep, its depth at the occi- 

 put being three fifths of its length; its upper surface longitudinally concave, the width of 

 the interorbital space being more than one-half of the longitudinal diameter of the eye. 

 Lye large, a little longer than deep, contained thrice and two-thirds in the length of the 

 head and equal to that of the snout. Infraorbital ring narrow, the broad and large maxil- 

 lary being separated from the orbit by a narrow strip of bone. Snout wedge-shaped, with 

 a pair of short and flat projections in front, each being formed by the intermaxillary and 

 toothed at its extremity. The (deft of the mouth is wide, the maxillary extending to below 

 the hind margin of the orbit. Dentition very feeble, all the teeth being minute and uni- 

 serial. The intermaxillary and maxillary are toothed throughout their whole extent: the 

 teeth of the mandible are particularly minute, and the series is interrupted close to the 

 symphysis, the syniphyseal portion being external to the lateral portion, which is implanted 



