Acanthopterygii ; Synentognathi 2 1 1 



the eastern United States, often ascends the rivers. Tylosurus 

 rapliidoma, Tylosurus fodiator, Tylosurus acus, and other species 

 are very robust, with short strong jaws. Athlennes hians is a 

 very large fish with the body strongly compressed, almost 

 ribbon-like. It is found in the West Indies and across the 

 Isthmus as far as Hawaii. Many other species, mostly belong- 

 ing to Tylosurus, abound in the warm seas of all regions. 

 Tylosurus ferox is the long torn of the Australian markets. 

 Potamorrhaphis with the dorsal fin low is found in Brazilian 

 rivers. A few fossil species are referred to Belone, Belone flava 

 from the lower Eocene being the earliest. 



The Flying-fishes: Exocoetidae. The family of Exoccetida? in- 

 cludes the flying-fishes and several related forms more or less 

 intermediate between these and the garfishes. In these fishes 

 the teeth are small and nearly equal and the maxillary is sepa- 

 rate from the premaxillary. The third upper pharyngeal is 

 much enlarged and there are no zygapophyses to the vertebrae. 



The skippers (Scombresox) have slender bodies, pointed jaws, 

 and, like the mackerel, a number of detached finlets behind 

 dorsal and anal, although in other respects they show no affinity 

 to the mackerel. The common skipper, or saury (Scombresox 

 saurus), is found on both shores of the North Atlantic swimming 

 in large schools at the surface of the water, frequently leaping 

 for a little distance like the flying-fish. They are pursued by 

 the mackerel-like fishes, as the tunny or bonito, and sometimes 

 by porpoises. According to Mr. Couch, the skippers, when 

 pursued, "mount to the surface in multitudes and crowd on 

 each other as they press forward. When still more closely 

 pursued, they spring to the height of several feet, leap over 

 each other in singular confusion, and again sink beneath. Still 

 further urged, they mount again and rush along the surface, 

 by repeated starts, for more than one hundred feet, without 

 once dipping beneath or scarcely seeming to touch the water. 

 At last the pursuer springs after them, usually across their course, 

 and again they all disappear together. Amidst such multi- 

 tudes for more than twenty thousand have been judged to 

 be out of the water together some must fall a prey to the enemy ; 

 but so many hunting in company, it must be long before the 

 pursuers abandon. From inspection we could scarcely judge 



