212 MSHES. 



f-f Skin with conical tubercles; teeth villiform; dorsal 1—4; 

 the spine tentacle -like, retractile into a cavity beneath a 

 prominent protuberance on forehead. 



Maltheidm, the Bea Bats. 

 ** Head high, compressed ; teeth card-like. 



Antennariidw, the Diablos. 



FAMILIES OF PLECTOGNATHI. 



* Jaws modified into a sort of beak, without distinct teeth. 



f Both jaws divided by a median suture (teeth fused into two 

 in each jaw); belly greatly inflatable. 



TetrodontidcB, the Puffers. 



ff Jaws without median suture ; belly scarcely or not inflatable. 



X Body scarcely compressed, spinous, with a distinct caudal 



fin Diodontidas, the Box Fishes. 



\X Body much compressed, very short, truncate ; the vertical 

 fins more or less confluent. 



Orthagoriscidm, the Oldbe Fishes. 

 ** Jaws with distinct teeth. 



a. Front teeth incisor-like; 1 to 3 dorsal spines; no carapace. 



Balistidm, the File Fishes, 

 aa. Teeth slender; no dorsal spines; body enveloped in a box- 

 like carapace, formed of hexagonal bony plates; snout, 

 bases of fins and tail free, covered with skin. 



OstraeiontidoB, the Trunk Fishes. 



FAMILIES OF LOPHOBRANCHII. 



* Tail prehensile, without caudal fin ; body abraptly contracted 



at base of tail ; head crested, out of line of axis of body. 



Sippocam/pidm, the Sea Horses. 

 ** Tail not prehensile, with a developed caudal ; body gradually 

 tapering; direction of head in a line with axis of body. 



Syngnathidm, the Pipe Fishes. 



OEDERS OF GANOIDEI. 



* Skeleton bony; body scaly; air bladder cellular, lunglike 



(Htoganoidbi). 

 f Scales cycloid ; snout short, broad. . Ctclogakoidei, CC. 



