122 PROCEEDINGS OF THE ACADEMY OF 



uniserial on each jaw. Branchiostegal rays only three on each side. Dorsal 

 fin nearly equally divided ; its spinous portion convex and with seventeen 

 spines, the last of which are lower than the second part. Anal fin oblong, 

 with three moderate spines and about fifteen gradually decreasing rays. Pec- 

 toral fins with one of its simple ra\s produced beyond the rest. 



The genus Nematodactylus is distinguished from all the other representatives 

 of the family by the presence of only three branchiostegal rays. Notwith- 

 standing this anomalous character, its resemblance to the Latridinse, and 

 especially to Chiredactylus and the allied genera, is such that scarcely a doubt 

 can be entertained as to the affinity of the genus to the rest of the subfamily. 

 Another characteristic feature cf the genus is the nudity of the cheeks. 



Only one species is known. 



Nematodactylus concinnds (Rich.) 



Nemadactylus concinnus Richardson, Transactions of the Zoological 

 Society, vol. iii. p. 116, pi. 4, fig. 2. 

 Habitat. Port Arthur, Van Diemen's Land. 



Description of a new species of CIRRHITUS. 



ClRRHITUS ALTERNATUS Gill. 



The form is similar to that of the typical species of the genus. The region 

 of greatest height is above the ventral fins, and there equals three-tenths 

 (3-10) of the total length ; thence the back is slowly decurved towards the 

 caudal peduncle ; the height behind the dorsal equals an eighth and that at 

 the lowest part of the peduncle a tenth of the length. The thickness at the 

 pectoral region is between a fifth and sixth of the length. 



The head is very obliquely decurved, and is longer than high ; it nearly 

 equals the height (29-100) to the end of the bony projection of the operculum, 

 and the membranous portion extends two fractions beyond (31-100.) The 

 distance from the snout to the nape equals 23-100 of the total length, and is 

 as great as the height at the latter region ; the height at the pupil equals 

 18-100 of the length. The interorbital region is channelled or concave. The 

 distance between the orbital ridges is less than the diameter of the eye (4^-100. ) 

 The eye is moderate, the diameter being nearly a fourth of the head's length 

 (7-100 of the total), and is greater than the height of the preorbital, which 

 is about a fifth of the head's length (6-100.) The snout exceeds a third of 

 the same (11-100.) The preoperculum has a convex margin, which is deli- 

 cately serrated above the interoperculum. The preorbital is entirely concealed 

 in the integuments and entire, and equals in height the diameter of the eye. 

 The cheeks are covered with very small scales ; the preopercular border naked ; 

 the operculum and suboperculum have three rows of scales, larger than those 

 of the body ; the interoperculum three in one row ; the operculum two in the 

 lower row and two smaller ones in an upper. The postnasal fringe has two 

 larger filaments and several smaller ones. 



The cleft of the mouth has a semi- elliptical contour, and is moderate, the 

 supramaxillary bones ending under the posterior border of the pupil. The 

 canine teeth are well developed, two being in the front of the upper towards 

 the sides, and six to eight in the lower in front, while on each side of the 

 lower are also two larger ones. The band of villiform teeth is quite broad in 

 each jaw. The front of the vomer only has a narrow lambdoidal band, and 

 the palatines are unarmed. 



The dorsal fin commences over the end of the bony operculum and the axilla 

 of the pectoral, or nearly with the third tenth (32-100) of the total length. The 

 spinous portion covers three- tenths (31-100) of the length, and is convex ; the 

 first spine equals a twentieth (5-100) of the total length, and is less than half 

 as long as the third to the sixth inclusive, they equalling a ninth (11-100) of 



[March, 



