180 THE VOYAGE OF H.M.S. CHALLENGER. 



Saurus haianus. 



Saurus kaianus, Giinth., Eeport on the Shore Fishes, Zool. Chall. Exp., pt. vi. p. 50, pL xxiii 



fig. C. 



Habitat. — Ki Islands, Station 192; depth, 140 fathoms. One specimen, 5|- inches 

 long. 



Harpodon, Les. 

 Harpodon microchir (PI. XL VII. fig. A). 



Harpodon microcliir, Giiath., Ann. and Mag. Nat. Hist., 1878, vol. i. p. 487. 



B. 17. D. 14. A. 14. P. 12. V. 9. 



Body elongate, compressed ; its greatest depth is below the origin of the dorsal fin, 

 and contained seven and a half times in the total length, without caudal. The caudal 

 peduncle is long and its least depth only one-third of that of the body. Vent situated 

 far backwards, its distance from the root of the caudal being only one-half of that from 

 the head. Head small, more compressed behind than anteriorly, the flat interorbital 

 space being one-fourth of the length of the head. The latter constitutes one-sixth of the 

 total length, without caudal. Snout very short, the diameter of the small eye being two- 

 fifths of its length and about one-eleventh of the length of the head. Bones of the head 

 thin and more or less flexible ; mandible extremely long, projecting in front, and nearly 

 three-fourths of the length of the head. 



Cleft of the mouth extremely wide, armed with numerous slender, more or less curved 

 teeth of unequal size, all of which are movable and depressible towards the median line 

 of the mouth. The maxillary is armed with a narrow band, of which the inner series 

 contains the larger teeth ; mandible armed with a similar band, but the larger teeth are 

 nearly three times the size of those of the upper jaw, and terminate distinctly in 

 an arrow-head-shaped point. Palatine teeth irregularly biserial and extending far 

 backwards ; the anterior are the strongest and strongly curved. There is inside this 

 long band of teeth a second much shorter one. The hyoid bone and the concave margins 

 of all the branchial arches above and below are armed with clusters and bands of teeth, 

 and considering the great distensibility of the mouth, this fish must be able to seize and 

 to retain fishes of very considerable bulk. 



The branchial apertures are exceedingly wide, the isthmus is narrow and compressed. 

 Gills four, pseudobranchise very distinct ; gill-laminse rather short. 



The dorsal fin occupies a position midway between the eye and the root of the caudal 

 fin ; it is not quite so high as long, and rather lower than the body underneath. The 

 small adipose fin is a little nearer to the caudal than to the dorsal, and opposite to the 

 middle of the anal fin, which is of a similar shape to the dorsal but lower. Caudal fin 



