Above blue; beneath silvery: abdomen spinous; each spine arising from a stellated root, of four rays. Don.
T. stellatus, Don. Brit. Fish. vol. iii. pl. 66. Turt. Brit. Faun. p. 116. Flem. Brit. An. p. 174. Globe Diodon, Penn. Brit. Zool. vol. iii. p. 132. pl. 20. Globe Tetrodon, Id. (Edit. 1812). vol. iii. p. 174. pl. 23.
* Brit. Zool. vol. iii. p. 141.
† Net. Hist, of Yarm. p. 18.
Entire length one foot seven inches; length of the helly, when distended, one foot; the whole circumference in that situation two feet six inches. Penn.
(Form). Body usually oblong, hut when alarmed the fish has the power of inflating the belly to a globular shape of great size: the whole surface of the abdomen, down to the vent, armed with small sharp spines, each arising from a distinct stellated root of four processes: mouth small: back from head to tail almost straight, or at least very slightly elevated: dorsal placed low on the back; anal opposite: caudal almost even, divided by an angular projection in the middle: pectorals present; ventrals wanting.
D. 11; A. 10; C. 6; P. 14.
(Colours). Back of a rich deep blue: belly and sides silvery white; the spines of a rich carmine-colour: tail and fins brown: irides white, tinged with red. Penn. and Don.
An individual of this species is recorded by Pennant as having been taken at Penzance in Cornwall. A second specimen, also captured on the Cornish coast, is figured by Donovan. Bloch appears to have considered Pennant's fish as his T. lagocephalus *, but by Donovan it was thought, and apparently with some reason, to be distinct. This and all the other species in this genus have the power of inflating the abdomen to a large size, at the same time that they erect the spines with which it is armed, by which means they defend themselves against the attacks of their enemies.