1. CENTEISCUS. 621 



The soft dorsal fin is liighcr than long, with the rays simple, the 

 middle ones being the longest ; its distance from the caudal equals 

 the length of its base. The anal fin commences immediately behind 

 the vent, vertically below the fourth dorsal si:)ine, and extends a little 

 more backwards than the soft dorsal ; it is, like that fin, composed of 

 simple rays, but much lower. The caudal fin is shorter than the 

 pectoral, slightly emarginatc posteriorly, and composed of nine rather 

 compressed and undi\-ided rays, the ethers on the upper and lower 

 sides of its base being rudimentary. 



The colour of the specimens is rose or reddish-olive on the back, 

 and silveiy on the sides and on the belly. 



The vertebral column is composed of eight abdominal and sixteen 

 caudal vertebra) ; the former are distinguished by their strength and 

 large size, a peculiarity A^'hich is in intimate connexion with the cir- 

 cumstance that they form the base of other strongly developed bones ; 

 their parapophyses are strong, rather long, and those of the first four 

 vertebrae have their extremities united. The bony strips, which are 

 visible externally, and which we have mentioned in the description 

 of the outward characters, are the modified ribs with their epipleiu'als. 

 The neural spines of the three anterior vertebra) are strong, espe- 

 cially that of the third, which corresponds to the interneural of the 

 second dorsal spine. Tliis interneural is situated behind the third 

 neural, and ends in three articular processes which receive two others 

 of the doi'sal spine between them. 



Another pecuHarity is the great breadth of the radius, this bone 

 forming mth its fellow a suture which is as long as the bone is high ; 

 there is an oval free space between the radius and the humerus. 

 The coracoid is very strong, straight, sabre-shaped, extending back- 

 wards to the pubic bones, which, however, are not fixed to it and 

 quite small. The bony plates forming the cutting mai-gin of the 

 abdomen and thorax are dermal productions, and do not belong to 

 the skeleton. 



2. Centriscus gracilis. 



Loive, Proc. Zool. Soc. 1839, p. 86, and Trans. Zool. Soc. iii. p. 12. 



B.4. D. 4-5 I 11. A. 18-19. P. 16. V. 5. C. 6-|-4-|-5 + 6. 



The height of the body is contained twice and three-fifths to three 

 times in the chstance of the operculum from the base of the caudal 

 fin. The second dorsal spine is rather strong, not (or very indi- 

 stinctly) denticulated posteriorly, its length being one-fourth or two- 

 ninths of the distance of the opcrcle from the caudal. 



Sea of Madeira. West coast of Africa. Coasts of Japan and 

 China. 



a-c. Half-grown. Mediterranean. Purchased of Mr. Frank. 

 (Z. Adult. ? Mediterranean. Purchased of Mr. Jamrach. 

 e. Adult. Madcii-a. Presented by the llev. H. H. Methucn. 

 /, g. Fine specimens. Sierra Leone. 

 h, i. Fine specimens. Japan. 



