FISHES. 17 



the only ones which require to be compared with atratus, are rubripes, pi. CXXIII. f. 1., and 

 firmamentum, pi. CXXVI. f. 1. Both differ from atratus in the mouth being at the extremity 

 of the head, and not the chin, and rubripes has the eye much more remote from the profile, 

 and large black marks on the flanks, while firmamentum, with a more arched back, has the 

 spines more generally diffused, and many pale oval or round spots equably placed on the 

 head, back, belly, and basal half of the caudal fin. None of the species named under 

 Cuvier's fourth division of the genus, characterized by smooth flanks, without tubercles, have 

 any resemblance to atratus. 



TETRODON HISPIDUS, Laccpede. 

 Le Tetrodon Mrisse, Lacep. vol. i. p. 487. pi. 24. f. 1. ? 

 Radii.— D. ]0; A. ; C. 9j; P. 17. 



Plate IX. Pig. 3-4. 



I refer this species, though not without doubt, to the Tetrodon hispidus figured by 

 Lacepede, from a drawing of Commerson's, but it seems to be distinct from the hispidus of 

 Block, which wants the white spots on the back. In retaining the specific name of hispidus, 

 I have followed the Regne Animal, though without expressing an opinion as to the identity 

 of Commerson's fish with the hispidus of the Nile and Mediterranean, which I have not 

 seen. 



This Tetrodon has a short thick snout, which in profile ascends to the prominent eyes. 

 The back is moderately arched, and the belly can be distended to a semi-globular form. 

 When the fish is fully blown up, the pectorals, dorsal and anal, are much concealed, as well as 

 a considerable portion of the caudal. The space between the eyes is equal to two diameters 

 of the orbits, and is slightly concave owing to the prominence of the upper borders of the 

 orbits. The nostrils are pierced in two short barbels, which are connected at the base. The 

 pectorals have an even or slightly crescentic edge, with rounded corners. The caudal is even, 

 and the dorsal is placed, nearly its own breadth, before the anal. The lips are papillated. 

 A ring round the mouth, the upper part of the snout, as far back as the nostrils, the narrow 

 borders of the eyes, a ring round all the fins, the fins themselves, and the tail, posterior to 

 the anal fin, are smooth. The rest of the integuments are spiny. The spines of the sides, 

 belly, and cheeks, are closely set and rigid, and though small, are conspicuous enough. Those 

 of the back are very short, scarcely penetrating the skin, and are not so numerous. They 

 extend backwards behind the dorsal, and terminate over the fore-part of the anal. 



The specimen, which has been long in spirits, has a grayish-brown colour above, and a 

 white belly. The upper parts are regularly spotted with white, the dots being round on the 

 snout, tail, and base of the caudal fin, and oval on the back. They coalesce into circular 

 lines round the eyes and bases of the pectorals and dorsal fins ; the bases, themselves, being 

 dark. The end of the caudal is blackish brown, and there are some dark tints on the dorsal. 



