94 •' THETIS " SCIENTIFIC RESULTS. 



of the snout and the dorsal rays, and nearer to the profile by one- 

 half its diameter; the gill opening is oblique, equal to and 

 separated from the eye by a diameter; it is situated beneath the 

 eye, and slightly in advance of the root of the pectoral. Nostrils 

 in a naked groove in front of and near to the eye. 



Teeth. — Two pairs in the lower jaw, each produced into an 

 angular point at its inner margin ; three projections are thus 

 formed, one median and two lateral. Three pairs in the upper 

 jaw, of which the two inner pairs are pointed ; behind this pair, 

 and between which its point appears, is another tooth on each side 

 with a spine-like apex ; five projections are thus formed, the inner 

 one, as in the lower jaw, furnished by two teeth. 



Upper profile of snout slightly concave, rather tumid in front 

 of the spine, whence it is flat, but rises considerably to the rays. 

 The anterior rays mark the highest point, thence it descends in a 

 gentle curve to the caudal pedicel. The lower profile is a perfect 

 arc described from the margin, one-fourth of the distance of the 

 dorsal rays from the spine, which arises in the anterior third of 

 the eye ; it is 1 '6 in the length of the head, not very strong, and 

 slightly curved backwards ; it is triangular in section, the anterior 

 ridge furnished with two series of small blunt spines set close 

 together ; at each posterio-lateral edge is a single series of spines. 

 Soft dorsal and anal low, the rays regularly increasing to the 

 sixth, which with the few following rays is the longest ; the anal 

 arises slightly behind the dorsal and terminates nearer the caudal. 

 Ventral spine immovable, very small, with a few points directed 

 before and behind, situated about an eye-diameter from the end 

 of the ventral bone, which is not extensible. Pectoral fin small, 

 one-fifth longer than the eye, placed beneath the orbit. Caudal 

 large and rounded, no shorter external rays, its pedicel compressed, 

 its height one-third the length of the head without spines or 

 bristles. 



Skin — Rubbed from head to tail the skin feels quite smooth, 

 and in the reverse direction very slightly rough ; under a half -inch 

 objective it is seen to be crowded with simple spines, which 

 measure 0'2 mm. in length. 



Colour yellowish, with wavy blue lines for the most part 

 horizontally disposed, anastomising at intervals, and forming 

 hexagonal figures, many of which enclose a brown blotch ; fins 

 uniform yellow. 



A I'eference to the type specimens shows that the colour pattern 

 of tlie young is to a large extent lost in adult examples. I liav(^ 

 tlu!refor(> drawn one of the tyj^es of the natural size. 



