8. nOLOCENTRUM. 31 



inches, lines. 



Length of fourth anal spine 1 U 



— — of first anal ray 1 5 



of last anal ray 5| 



3. Holocentnmi macropus. (Plate I. tig. B.) 

 D. n 1 15. A. i L. lat. 52. L. transv. 4/7. 



Body rather elongate. Ventral fins very long, as long as the 

 head. Operculum with a very strong spine, and a veiy small one 

 beneath ; pra^opercular spine moderate, one-thii'd of the length of 

 the posterior margin of pi-ajoperculum. 



a. Adult : stuffed. Isle de France. Pui'chased of Sii' A. Smith. 



Description of the sj}ecimen. — Although the greater part of the this 

 in the specimen are injui'ed, I do not hesitate to found on it a species, 

 as the ventrals are well preseiTed, and offer a character whereby it 

 may be distinguished from eveiy other species of the genus. In the 

 measiu'ements given in this species, the total length is to be understood 

 from the snout to the root of the caudal fin only, as this fin is nearly 

 entirely lost. 



The height of the body is nearly equal to the length of the head, 

 and 35^ in the total ; the interspace between the eyes is 6-i- in the 

 length of the head ; the two bony ridges radiate behind in about 

 ten branches. The snout is pointed, its length being -Iths of the 

 diameter of the eye ; the groove for the processes of the inter- 

 maxillaiy bones is stiU shorter ; the tui-binal bone does not termi- 

 nate in an anterior prominent spine ; the upper maxiUary reaches 

 not quite to below the middle of the eye. The diameter of the eye 

 is 2>f in the length of the head ; all the surrounding infraorbital 

 bones are serrated, and the anterior is armed in front ■with a veiy 

 strong cui'ved tooth. The operculum is distinctly striated, the striae 

 terminating in fine marginal points ; the upper spine is very 

 strong, as in H. furcatum, whilst the inferior resembles more one 

 of the other denticulations. The suboperculum has also some stride, 

 terminating in spinous points, coarser than those of the operculum. 

 Interoperculum striated and serrated. Both the edges of the prse- 

 operculum are finely serrated, Kke the operculum ; the spine at the 

 angle is of moderate length. 



The thii'd, fourth and fifth dorsal spines are longest, nearly one- 

 half the height of body. The soft dorsal has no spine in front, and 

 does not appear to have been elevated. The caudal fin has been 

 forked. The first spine of the anal is minute, the second smaller 

 than the opercular spine, the third strongest, scarcely longer than 

 the longest of the dorsal fin, the fourth is a little shorter than 

 the foui'th ; the first ray is rather elongate, and higher than the 

 longest of the dorsal fin. The pectorals are short, and probably 

 have not reached further than to the level of the eleventh or twelfth 

 scale of the lateral Une. The ventral fins are formed by one spine 



