Series Plectognathi 419 



regards, having the body compressed and covered with rough 

 scales The teeth form a single plate in the lower jaw, but 

 are divided on the median line above. The compressed, fan- 

 like, ventral flap is greatly distensible. Triodon bursarius, 

 of the East Indies and northward to Japan, is the sole species of 

 the family. 



The Globefishes : Tetraodontidae. In the Tetraodontidce (globe- 

 fishes, or puffers), each jaw is divided by a median suture. 

 The dorsal and anal are short, and the ventrals are reduced 



FIG. 356. Silvery Puffer, Lagocephalus Icevigatus (Linnaeus). Virginia. 



in number, usually fifteen to twenty (7 + 13 to 7 + 9). The 

 walls of the belly are capable of extraordinary distension, so 

 that when inflated, the fish appears like a globe with a beak 

 and a short tail attached. The principal genus Spheroides 

 contains a great variety of forms, forming a closely intergrad- 

 ing series. In some of these the body is smooth, in others more 

 or less covered with prickles, usually three-rooted. In some 

 the form is elongate, the color silvery, and the side of the belly 

 with a conspicuous fold of skin. In these species, the caudal 

 is lunate and the other fins falcate, and with numerous rays. 

 But these forms (called Lagocephalus} pass by degrees into 

 the short-bodied forms with small rounded fins, and no clear 

 Hne has yet been drawn of the generic of this group. In these 

 species each nostril has a double opening. Lagocephalus lago- 

 cephalus, large and silvery, is found in Europe. Lagocephalus 

 Icevigatus replaces it on the Atlantic Coast of North America. 

 In Japan are numerous forms of this type, the venomous 

 Lagocephalus sceleratus being one of the best known. Numerous 

 other Japanese species, Spheroides xanthopterus, rubripes, 

 pardalis, ocellatus, vermiculatus, chrysops, etc., mark the 



