40. PLATYCEPHALUS, 179 



axis, horizontally or obKquely directed inwards : the posteinor sym- 

 physis of the pubic bones is coincident \vith the interior extremities 

 of this axis. The difference between the three genera is merely this : 

 that whUst in Coitus the space between the axes is entirely, and 

 in Trigla partially closed by a very thin bony plate, it remains open 

 in Platyceplialus. 



There are twelve abdominal and fifteen caudal vertehrce, the length 

 of the former portion of the vertebral column being to that of the 

 caudal as 1:1-7. The single vertebrae are rather elongate ; the 

 anterior twelve have ribs. The haemal, neural, &c. spines are feeble, 

 strongly depressed. 



The teeth are small, cardiform ; the anterior portion of the inter- 

 maxillary is provided posteiiorly with some stronger ones. The teeth 

 of the vomer form a very narrow, unintcrriipted, convex band ; those 

 of the palatine bones are in a single series. 



2. Platycephalus tasmanius. 



Richards. Trans. Zool. Soc. iii. p. 97, aud Voi/. Ereb. S,- Terr. Fishes, 

 p. 23. pi. 18. f. 1, 2. 



D. 1 I 7 I 14. A. 14. L. lat. ca. 115. 



The length of the head is Z\ in the total, and its width between 

 the praeopercular spines 1| in its length. The space between the 

 eyes is slightly concave, and one-third the length of the snout. The 

 upper surface of the head is flat, the ridges being scarcely prominent. 

 Two prseoperciilar spines of moderate size, the upper one considerably 

 shorter than the lower. The length of the second dorsal spine is 

 rather less than one-half of that of the head. Lateral line smooth. 

 The posterior portion of the caudal black. 



Coast of Van Diemen's Land ; Port Jackson. 



a. Adult. Van Diemen's Land. From the Haslar Collection. 



h. Adult. Port Arthur. From the Haslar Collection. 



c. (?) Half-grown. Madras. Presented by T. C. Jerdon, Esq., M.D. 



d. Adidt. From the Haslar Collection, "j 



e. Adult. From the Haslar Collection. m c i.\. 



f. Adult. From the Haslar CoUection. -^^^^'^ ^^ ^^^ «P^^^^^- 

 fj. Adult. From the Haslar Collection. J 



Ji. Adult. Presented by J. B. Jukes, Esq. 



3. Platycephalus laevigatus. 



(Juv. ^ Val. iv. p. 248 ; Quay §• Gaim, Voy. Astro/. Poiss. p. 684. 

 pi. 10. f. 4. 



D. 1 I 8 I 14. A. 14. 



Head with the ridges scarcely visible, and without any spines ; the 

 upper praeopercular spine is twice as long as the lower. The space 

 between the eyes is one-half only of their vertical diameter. Brown 

 above, white below ; anal white, the rays of the other fins spotted 

 with brown. 



Port Western. 



s2 



