152 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 



1. Tetrodon aerostaticus. Jen. 



T. capite, dorso, lateribus, et pinna caudali, nigro-maculatis ; ventre turgidissimo, 

 fasciis obliquis nigris : corpore uudique muricato, caudd solum exceptd : capite 

 brevi ; fronte inter oculos paululum depresso : maxillis cequalibus : lined laterali 

 nulla : pinna dorsali omnino ante analem positd : pinna caudali subrotundatd. 

 D. 11 ; A. 10; C. 10; P. 11. 

 Long. unc. 2. lin. 0. 



Form. — Head short. Body approaching to globular, with the skin of the belly extremely loose and 

 capable of great inflation ; every where beset with minute prickly asperities, the extreme end 

 of the tail alone excepted. Crown nearly flat, very slightly depressed between the eyes. 

 Jaws equally advanced. Nostrils tubular. No appearance of any lateral line. Dorsal en- 

 tirely in advance of the anal : both these fins small. Caudal slightly rounded. 



Colour. — {In spirits.) Head, back, and sides to the depth of the pectorals, greyish brown, spotted 

 with black ; the spots very small and crowded on the back, but becoming larger on the flanks 

 and tail. Belly white, with deep black oblique broad bands, inosculating in some places, so as 

 to form large meshes. Dorsal, anal, and pectorals, plain ; but the caudal very elegantly and 

 distinctly spotted. 



The ticket attached to this specimen has been lost, and its locality is in con- 

 sequence unknown. In general appearance, it very much resembles the T. lineatus 

 of Bloch, of which it may possibly be a variety ; but it would seem to differ from 

 that species, in having the forehead less elevated ; in wanting the lateral line 

 altogether, of which I can discover no trace ; and in having the whole back and 

 upper part of the sides spotted, and not merely the tail and its fin, as is repre- 

 sented in the T. lineatus. 



2. TETRODON IMPLUTUS. Jen. 



T. sordide melallico-olivaceus, maculis circularibus albis ; venire albo, liueis olivaceis 

 longitudinalibus, haud admodum turgido : corpore suboblongo, magna ex parte Icevis- 

 simo, ventre solum muricato : maxillis subcequalibus : naribus tubulosis, bifurcatis : 

 lined laterali distinctd,parum tortuosd : pinna dorsali anali paulo anterior e : pinna 

 caudali cequali. 



D. 10; A. 10 ; C. 11; P. 10. 

 Long. unc. 4. lin. 9. 



Form. — Approaching to oblong, the belly a little ventricose. Head not so short as in the last 

 species, nor yet much produced. Body every where smooth, excepting the middle of the 

 abdomen from beneath the pectorals to the vent, and not very prickly here. Top of the head 

 slightly depressed between the eyes. Jaws nearly equal ; the upper one, if any thing, a very 

 little in advance. Nostrils tubular, the tubes forked from the bottom into two equal branches. 



