8. UOLOCENTlUJll . l^] 



inches, lines. 



Length, of fourth anal spine 1 



of fii-st anal I'ay 1 5 



of last anal ray 5^ 



3. Holocentrum macropus. (Plate I. fig. B.) 

 D. 11 I 15. A. ± L. lat. 52. L. transv. 4/7. 



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

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

 beneath ; prteopereular spine moderate, one-third of the length of 

 the posterior mars:in of prajoperculum. 



a. Adult : stuffed. Isle de France. Purchased of Sir A. Smith. 



Description of the specimen. — Although the greater part of the fins 

 in the specimen are injured, 1 do not hesitate to found on it a species, 

 as the ventrals are well preserved, and ofter a character whereby it 

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

 measurements given hi this species, the total length is to be understood 

 from the snout to the root of the caudal Jin onli/, as this fin is nearly 

 entirely lost. 



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

 and 3f in the total ; the interspace between the eyes is ()i in the 

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

 ten branches. The snout is pointed, its length being ^ths of the 

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

 maxillary bones is still shorter ; the tui'binal bone docs not teraii- 

 nate in an ariterior prominent spine ; the upper maxillaiy readies 

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

 is 3^ in the length of tlie head ; all the surrounding infraorbital 

 bones ai'e serrated and the anterior is armed in front with a very- 

 strong curved tooth. The operculum is distinctly striated, the striai 

 terminating in fine marginal points ; the upper spine is very 

 strong, as in ff. furratum, whilst the inferior resembles more one 

 of the other denticulatibns. Tlic suboperculum has also some striae, 

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

 Interoperculum striated and scrrotcd. Both the edges of the praj- 

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

 angle is of moderate length. 



The third, foiu'th 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 sftialler 

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

 the longest of the dorsal fin, the fourth is a little short(u- than 

 the fourth ; the first ray is rather elongate, and higher than the 

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

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

 scple of the lateral line. Tlie vcntrnl fins are formed by one spine 



