502 
ACTINOPTEETGII. 
p. Ill, pi. iii. fig. 1 (? errore).— Oligocene ; Canton Glarus, 
Switzerland. [Imperfect fish; Geological Museum, Uni¬ 
versity of Bonn.] 
Acanus gracilis, G. vom Bath, loc. cit. 1859, p. 112, pi. iii. fig. 2 ; 
A. Wettstein, loc. cit. 1886, p. 66, pi. viii. fig. 9.—Ibid. 
[Ditto.] 
(t' Genus LATES, Cuvier & Valenciennes. 
[Hist. Hat. Poissons, vol. ii. 1828, p. 88.] 
Head and trunk laterally compressed. Mouth large and protrac¬ 
tile, with bands of villiform teeth on the premaxilla, dentary, 
vomer,palatine, and ectopterygoid; supramaxillapresent; suborbitals 
reduced and serrated. Upper limb of preoperculum serrated, lower 
limb with few large spines (some antrorse), and angle with a strong 
spine; operculum with one spine behind; seven branchiostegal 
rays. Vertebrae 12 in the abdominal, 13 in the caudal region; 
some hinder ribs borne by transverse processes. Two dorsal fins 
subequal in extent and connected at the base, the anterior with 7 
or 8 spines, the posterior with one spine and 10 to 12 articulated 
rays ; anal fin small, with 3 spines and 8 or 9 articulated rays ; 
caudal fin rounded or slightly forked. Scales large or of moderate 
size, finely denticulated, extending partly over the head, also partly 
ensheathing the dorsal and anal fins. Lateral line complete, ex¬ 
tending over the caudal fin. 
The existing species of Lates inhabit the freshwaters of tropical 
Africa, and the mouths of rivers and coasts of south-eastern Asia 
and northern Australia. 
Lates gracilis, Agassiz. 
1796. Holocentrm calcarifer, G. S. Volta, Ittiolit. Veronese, p. Ixxxii. 
pi. xvii. fig. 3 {errore). 
1796. Lutianus ephipphim, G. S. Volta, ibid. p. ccxxxv. pi. Ivi. fig. 4 
(errore). 
1833-34. Lates gracilis, L. Agassiz, Poiss. Foss. vol. iv. p. 25, pi. iii. 
1833-34. Lates gibhus, L. Agassiz, ibid. p. 27, pi. iv. [Distorted fish,] 
1833-34. Lates noixeus, L. Agassiz, ibid. p. 29, pi. v. [Imperfect dis¬ 
torted fish ; Palaeontological Museum, Munich.] 
1876. Lates gracilis, F. Bassani, Atti Soc. Veneto-Trent. Sci. Hat. 
vol. iii. p. 174. 
1876. Lates gibhus, V. Bassani, ibid. p. 174. 
Type. "Well-preserved fish ; Paris Museum of Hatural Histor}'. 
A species attaining a length of about 0-25. Length of head 
