3. TUACnicnTUYs. 11 



of the jaws and palatine bones in narrow l)ancls, and those of the 

 vomer in a small patch. 



The interspace between the eyes is one-third of the length of 

 the head, and convex ; the scales of the nape extend nearh' to 

 above the middle of the eye. The remainder of the upper surface of 

 the head is scaleless, and occupied by cavities. There arc two narrow 

 bony ridges running from the nape to the front of the snout ; they 

 converge in the middle, including posteriorly a narrow triangidar 

 cavity. Between these lidges and the superciliary margin there is on 

 each side another ridge, slightly arched, and running from the supra- 

 scapulary to the posterior nostril ; there is a pair of large cavities 

 between these and the inner ridges ; lastly, there is a third cavity be- 

 tween the ridge just mentioned and the superciliary arch. This latter 

 cavity is absent in Beri/x ajjinis, the outer ridge and the superciliary 

 margin being confluent in that species. The nostrils are close 

 together ; the anterior small, round ; the posterior larger, short, 

 ovate. The eye is placed high up the sides, its cUameter is nearly 

 one-third of the length of the head. The infraorbital arch is trans- 

 formed into a channel, covered by a half- transparent skin, like the 

 cavities of the skull ; several bony ridges cross it ; the anterior 

 infraorbital is very narrow in front and scarcely denticulated ; none 

 of the bones extend to the proeoperculum. 



The operculum is not twice as high as Avide ; no scales are visible 

 on it, except at its upper extremity, but broad ridges, rough and 

 slightly arched ; the spine at its upper angle Ls scarcely visible. 

 The suboperculum is entire, and notched before the pectoral ; the 

 interoperculum is rough and slightly serrated. The pra^operculum 

 has on the hinder and under part two j^arallel ridges with a channel 

 between ; they are slightly roughened and meet at a right angle, 

 where there is a projecting triangular spine with a sharj) l)onj' ridge ; 

 the edges of this spine have a fine, hardly visible serrature. The 

 spine does not extend to the gill-opening. Cheek scaly. The scapu- 

 lary bone has a distinct spine, much more feeble than in the other 

 species. Humeral bone not serrated. 



The dorsal fin is placed somewhat nearer the base of the caudal 

 than the tip of the snout ; its height equals its length. The spines 

 and rays are much more slender than in Trachichtht/s (tnstrnlis, and 

 not roughened. The spines become long'er behind ; the fourth is 

 about as long as the last ray, one-half of the longest ; the longest 

 ray is the third, much longer than one-half of the depth of the body. 

 The caudal is moderately forked, with pointed lobes of moderate 

 length, aboixt one-fifth of the total. The origin of the anal falls 

 under the end of the dorsal, it is rather higher than long, but much 

 lower than the dorsal ; the spines and rays arc smooth, the former 

 gradually becoming longer lichind ; the third spine is much sliorter 

 than the first ray (which is the longest), and even somewhat sliorter 

 than the last. The pectorals are slightly rounded, short, their length 

 being one-seventh only of the total. The ventrals equal the ])e(torals 

 in length ; they are inserted a little behind the pectorals ; their spine 

 is equal to the third of the anal fin. 



