THE FISHES OF NEW JERSEY. 361 



Sub-Order GYMNODONTES. 



The Puffers. 



These are degraded plectognaths without spinous dorsal, dis- 

 tinct teeth, or scales. 



Key to the families. 



a. Caudal region normal, caudal peduncle developed 



h. Jaws divided by median suture, maxillaries and dentaries each curved 

 outward behind premaxillaries. tetrodontid^ 



hh. Jaws undivided, premaxillaries and dentaries co-ossified into suture- 

 less arches. diodontid.^ 

 aa. Caudal region aborted, body trunciated behind dorsal and anal; jaws 

 without median suture. molid^ 



Family TETRODONTID^. 



The Puffers. 



Body oblong or elongate, usually little compressed, sometimes 

 very broad. Head and snout broad. Each jaw confluent, form- 

 ing a sort of beak, which in each jaw is divided by a median 

 suture. Maxillaries curved outward behind premaxillaries. Lips 

 full. Nostrils various. Gill-openings small, placed close in front 

 of pectorals. Medifrontals articulated with supraoccipital, post- 

 frontals confined to sides, ethmoid more or less projecting in 

 front of frontals. Postfrontals extending outward as far as 

 frontals. Prosethmoid short and narrow, little prominent to view 

 above. No ribs. Vertebrae few, 7 or 8 -]- 9 to 13. Caudal ver- 

 tebrae normally developed. Air-vessel present. Belly capable of 

 great inflation. Skin scaleless, usually more or less prickly, 

 spines or prickles usually weak and movable, not rooted. Skin 

 armed with bony scutes forming a sort of carapace sometimes. 

 Spinous dorsal and ventral wanting, fins composed of soft rays 

 only. Dorsal posterior, opposite and similar to anal. Caudal 

 distinct. Pectorals short, broad, upper rays longest. Ventrals 

 none, pelvic bone undeveloped. 



