204 PEDICULATI. 



Halieutsea stellata, Cm. Sf Val. xii. p. 456. pi. 366 ; Faun. Japon. 

 Poiss. p. 160. pi. 72 ; Bleek. Amb. ^- Cer. p. 279. 



B. 5. D. 4. A. 4. C. 9. P. 13. V. 1/5. Vert. 7/10. 



Base of each spine with four or more radiating ridges. Uniform 

 rose-coloured. 



Seas of China and Jajjan. 



a. Adult. Purchased of Mr. Frank. 



b-c. Half-grown. From the Collection of the Zoological Society. 



d. Young. China. Presented by Captain Sir E. Belcher, C.B. 



e. A great number of dried specimens. From Chinese insect-boxes. 



f. Skeleton. Presented by Dr. Albert Giinther. 



Skeleton. — From an examination of the skeleton, it becomes very 

 evident that HalieuUm is most closely allied to Malthe, both genera 

 representing each other in different regions. The general arrange- 

 ment of the bones is the same, except that they are somewhat more 

 ossified in Halieutcfa — large portions of them, however, remaining 

 veiy thin and membranaceous. The cranial and facial portions of the 

 skiill are not of much extent, the great width of the head being 

 caused by the development of the opercles and of the humeral arch. 

 The skull proper is depressed and of moderate length. The crown of 

 the head is ilat, broad, siibpentagonal, with two low ridges which 

 are convergent postei'iorly. The orbital edges are much elevated, the 

 space between them being a deep groove, in which the bony portion 

 of the rostral tentacle (dorsal spine) is situated ; anteriorly the two 

 ridges are united, forming a bridge, below which the tentacle moves : 

 the whole of these orbital ridges are armed with erect spines. 



The jaw-bones are feeble : the maxillary is not dilated, and ex- 

 tends as far backwards as the intermaxillary; the intermaxillary 

 has long articulary processes, and another slender process arises from 

 the middle of its body ; the arch formed by the two mandibles is 

 nearly semicircular. Head of the vomer very broad and flat ; base 

 of the cranium rather convex. 



A series of strong bones forms the lateral margin of the head, and 

 extends from the forehead to the carpal bones. The -vthole of this 

 bony ring is covered with spines, either firmly adherent to the 

 bones or loosely attached to them ; it is formed by the pra?frontal, 

 prfporbital, interoperculum, part of suboperculum, and, finally, by 

 two or three dermal bones intercalated between the suboperculum 

 and the carpus. This union of the interoperculum with the prae- 

 orbital is very singtdar, and unique in this order of fishes. A little 

 before the sutiu-e between the inter- and suboperculum, the prae- 

 operculum is joined to the former ; it is the smallest of all the oper- 

 cular pieces, and its limbs meet at a somewhat aciite angle. The 

 suboperculum is composed of two portions : the lower is thick, joined 

 to the interoperculum, and forms the base for the upper portion, 

 which is large, subrhombic. lamelliform. The operculum is com- 

 posed of two styliform branches meeting at an acute angle, and 

 leaving between them a space filled up by a membrane ; the upper 



