BY J. DOUGLAS OGILBY. 25 



folded. Stomach simple, its posterior half with coarse, 

 gizzard-like longitudinal ridges within. Posterior processes of 

 premaxillaries not extending to the frontal bone ; frontal bone 

 with a pair of conspicuous ridges which are divergent in front, 

 mesially united by a bony bridge, and abruptly bent outwards so 

 as to form a deep loop with the tympanic ridge ; coronal ridges 

 well developed, continuous with the interfrontal bridge, and 

 united posteriorly to form a strong median crest for the first 

 dorsal spine, which is deeply grooved anteriorly ; suborbital 

 stay with two smooth parallel ridges, which are branched 

 posteriorly. Vertebrae 8 + 16 == 24. (Aeios, smooth ; Kpaviov, 

 skull). 



Coast of Queensland. Monotypic. 



In the obsolescence of the first soft ray of the ventral fins 

 this genus agrees with Daia. 



LlOCEANIUM PR^POSITUM, Sp. nOV. 



D. xiii 7. A. iii 5. 

 Depth of body greatest below the fourth dorsal spine, 

 where it is 2^ to 2|- in the total length ; length of head 2|- to 2f 

 in the same. Length of snout 1^ to If in the diameter of 

 the eye, which is 2f to 2^ in the length of the head. Width of 

 interorbital region 5i to 6 in the head. Maxillary extending to 

 the vertical from the posterior border of the orbit, its length 

 about 2 in the head, the width of its distal extremity about half 

 the diameter of the eye. Posterior preopercular spine extending 

 backwards to or a little beyond the vertical from the hinder 

 margin of the pupil, its length from the base of the anterior spine 

 4f to 5 in that of the head. Upper preopercular spine not quite 

 so long as the second preorbital spine. Gill-rakers 3 -f 9, a few 

 near the hinge claviform, the rest tubercular. Length of soft 

 portion of dorsal fin 3^ to 3^ in that of the spinous, the outer 

 border of which is sinuous ; third spine the highest, 

 twice as high as the first and conspicuously higher than 

 the second. If in the length of the head ; behind the third 

 the spines decrease in height to the sixth or seventh, and 

 then rise to the last, which is but little less than the third 

 and inappreciably more than those immediately preceding it,* 



*The tips of the spines are very fragile and easily broken off, but from 

 a comparison of three specimens the above appears to be the normal 

 sequence in height. In all the fourth spine is apparently lower than the 

 third or fifth, but this may not be the case with perfect examples. 



