HIPPOCEPHALUS JAPONICUS. 151 



37 plates in the inferior and 35 in the superior longitudinal 

 row. Between them lies the median lateral series, bear- 

 ing the lateral line, a nearly continuous row of 38-39 

 spineless plates extending from head to base of caudal (a 

 few of them with small blunt tubercles). The dorso- 

 lateral series is composed of small indistinct plates from 

 occiput to beyond middle of first dorsal, where they be- 

 come larger and spinous. The plates of the sixth, sev- 

 enth, eighth and ninth pairs behind the last ray of second 

 dorsal are closely approximated, but do not form single 

 median plates; from the ninth pair to the caudal the plates 

 of the two rows alternate, as on the ventral surface. 

 There are almost complete series of small plates, alter- 

 nating with the large ones, between the dorso- and superior 

 lateral series, between the superior and median lateral, 

 between the median and inferior lateral and between the 

 inferior and ventro-lateral series. This multiplication by 

 intercalation of small plates is evident all over the body. 

 There are no large but numerous minute plates in front 

 of and on base of pectorals. Gill-membranes posteriorly 

 and medially with several rather weak plates and many 

 minute plates and prickles, anteriorly and laterally with a 

 few small plates ; under side of lower jaw with many im- 

 perfect plates or strong prickles ; weaker prickles along 

 the branchiostegal rays. 



Head depressed throughout, narrow to the posterior 

 border of the orbits, behind which it widens rapidly. 

 Depth behind orbits | and over opercles 7^ of the width at 

 the same points. Orbits large, oval, ^j4 in head, far for- 

 ward. Interorbital space a little concave, very broad: at 

 anterior border of orbits wider than the orbit itself, 3^ 

 in head, at posterior border of orbit 2% in head. Su- 

 praorbital ridges expanded into a flat triangular shelf 

 projecting upward and outward over eye and ending 



