198 " ENDEAVOUR " SCIENTIFIC RESULTS. 



Ridges of the head fairh" well defined, Ijut low and smooth, 

 not terminating in spines. A small anterior orbital spine. 

 Interorbital spa.ce flat, the orbital margins upraised. Pre- 

 operculum with two stout spines, the upper oblique, the lower 

 slightly the longer. Opercular ridges ending in minute spines, 

 sometimes obsolete. Anterior nostril tentacular. Maxillary 

 reaching back to below the anterior third of the eye. Teeth 

 villiform in the upper jaw, arranged in a band, enlarged near 

 the symphysis, a few being canine-like. They are small, and 

 in several rows on the anterior portion of the mandible, 

 becoming larger and uniserial posteriorly. A group of canines 

 on either side of the vomer, joined by an arched row of smaller 

 ^eeth. A single row of large teeth on each palatine, with a 

 secondarv series of minute ones outside them. 



l,.''-^"'^^ 





r/^.' 



Fig. ]. Plaiijcephalus marmoratus. StoA(\. 



Body covered with small, ctenoid scales, whichjare also 

 present on the operculum and post-orbital portion of the 

 preoperculum. Lateral line scales not differentiated from the 

 others, unarmed ; about sixty-five bear tubules, and there are 

 about one hundred and ten rows of scales above the lateral 

 line. 



Origin of the first dorsal well behind the ends of the opercles ; 

 anterior spine small but distinct, the third the highest ; second 

 ray highest, as long as or a httle shorter than the third spine, 

 the others decreasing l^ackwards. Origin of anal a little before 

 that of the second dorsal ; its rays are lower, and they increase 

 shghtly in length brckwarcls. Pectorals reaching to below the 

 middle of the first dorsrl : the seventh upper ray longest, the 

 others decreasing regularly. Ventrals reaching the origin of 

 the anal. Caudal sub-truncate, or slightly rounded. 



Colour. — In formahn, brown above, the head with more or 

 less distinct Ught, dark-edged areas which are symmetrically 

 disposed. Back with five broad darker crovss-bands, the first 



