82 PROCEEDINGS OF THE ACADEMY OF 



II. Preoperculum entire. 



Scales 2026 Apogonichthys. 



5 



Scales 40 (Apogon aprion, Rich.) Glossamia. 



13 



As there is no gradation from one type to the other among the great num- 

 ber of species already known, the characteristics above given appear to be the 

 indices of distinct genera. Amia and Apogonichlhys are probably the most 

 closely allied groups. 



Family SPAROIDJE (Cuv.) 



Subfamily XENICETHYINJE Gill. 



XENICHTHYS Gill. 



Body moderately elongated and subfusiform, compressed, and with the 

 caudal peduncle also compressed and robust. Scales deciduous, rather 

 small, high and ctenoid. Lateral line tubular, in more conspicuous scales. 

 Head compressed, conic, longer than high, with the occipito-rostral outline 

 rectilinear. Upper surface of head to the nostrils covered with small scales. 

 Occipital crest prominent. Eyes circular, large, and mostly in the anterior 

 half of the head. Preorbital bones rather narrow and oblique. Operculum 

 with two spines. Preoperculum pectinated behind, the teeth higher up pro- 

 gressively directed upwards. 



Mouth rather small, with the lateral cleft very oblique, and not con- 

 tinued to eye ; supramaxillary bones broad, enlarged in front below the 

 intermaxillary, and behind the latter covered by a cutaneous flap from it. 

 Lower jaw shorter than upper, but with the chin projecting beyond it, and 

 with a pore on each side of the symphysis. Lower lip continuous and free at 

 symphysis ; plicated behind, where it is received under the upper jaw. 



Teeth small, recurved, and in rather narrow bands on each jaw. Vomer 

 with its projecting front provided with a villiform rhomboid patch; palatine 

 bones and tongue edentulous. 



Nostrils above anterior, and in a line with upper margin of orbit, near each 

 other; the anterior circular: the posterior cleft transversely. Branchiostegal 

 rays seven on each side. 



Pseudobranchise present. 



Dorsal fins connected by a low membrane at the base; the first with ten 

 rather slender but perfectly rigid spines ; the third, fourth and fifth of which 

 are longest, (with no recumbent spine in front) ; the membrane has a fibrous 

 appearance. Second dorsal lower than the first, and elongated. Anal fin 

 about as long as second dorsal, but rather farther back, with three small, 

 regularly increasing spines. Caudal fin emarginated, with rounded lobes. 



Pectoral fins small, with the upper angle produced, but apparently rounded. 

 Ventral fins inserted close behind the pectoral : each with a spine and five 

 branched rays, and a pointed axillar scale. 



As there might be some doubt as to the affinities of this genus, on account 

 of the few palatal teeth and the number of branchiostegal rays, an extended' 

 description of its generic characters has been given. The spinous dorsal be- 

 ing received in a groove, the upper jaw closing under the preorbital bones 

 and axillar ventral scales existiug, it belongs to the family of Sparoids, as 

 now modified. It cannot be referred to the Sciaenoids, as its skull is smooth. 

 The nearest allied genus appears then to be Moronopsis, [Dules marginatus 

 C. V.*) That genus differs in its more compressed body, the scales and the 

 similarity of those of the lateral line to the others, the stouter dorsal spines, 



* The Dates auriga and D.flauiventris are, of course, not regarded as allied to D. marginatus , 

 &c. I am unable to perceive any affinity between them, and they have been united only in accord- 

 ance with an artificial system. 



[Mar. 



