body is contaiiie 1, wlieu tlio pubic bone is extended, two and two- 
tliird times in the total length ; the two front teeth are triangular 
and by their union form a pointed edge ; the others are also 
pointed; the body is entirely covered with a very fine velvety 
granulation. 
The colour is entirely of a light and rather brilliant green, 
darker on the back, rather yellow on the belly ; the eyes and 
teeth are also green ; the caudal of the same colour ; second 
dorsal and anal transparent, rather dark on the edge. 
Only seen once in the month of March ; it is rather over two 
and a-half inches long, and has an oval form. 
Nota. None of the three sorts of Monaoanthus, I here describe, 
have any particular spines or spots on the sides of the tail. 
GYMNODONTES. 
“ Body more or less sliorteiied. The hones of 
the upper and lower jaw are confluent, forming a 
heah with a trenchant edge, without teeth, with or 
without medium suture. A soft dorsal, caudal, 
and anal are developed, — approximate. No spinous 
dorsal. Pectoral fins, no ventrals. 
“ Marine fishes of the temperate and tropical 
regions. Some species confined to fresh water.” 
Group TETBOBONTINA. 
Tail and caudal fin distinct. Bart of the oesophagus much exten- 
sible, and capable of being filled with air ; no pelvic bone ; air- 
bladder present. 
TETRODON. 
Eound in all the warm or tropical seas of the world. They are, 
generally poisonous. I have observed two sorts on the shores of 
Hobson’s Bay. 
