April, 1910. Fishes of Chicago — Meek and Hildebrand. 295 



Order HaplOltli. 



Pike-like Fishes. 



Skeleton bony; anterior vertebrae distinct; ventral fins abdom- 

 inal, rarely wanting; all of the fins of soft rays; no adipose fin; pec- 

 toral arch suspended from the skull; mesocoracoid wanting; oper- 

 cular bones well developed ; air bladder with a distinct duct. 



a. Lateral line present; jaws long and with large canine-like 

 teeth. EsocidcB, 295 



aa. Lateral line wanting; jaws without canine-like teeth. 



b. Upper jaw not protractile. Umbridcs, 297 

 bb. Upper jaw protractile. Pceciliidcz, 298 



Family E^oeiclse. 



The Pikes. 



Body elongate, somewhat compressed posteriorly; scales small, 

 cycloid; top of head naked, its sides partly scaled; ventral fins ab- 

 dominal; mouth large; premaxillaries not protractile; jaws, vomer, 

 palatines, and tongue with teeth; stomach not coecal; no pyloric 

 cceca; air bladder simple, with distinct duct. 



Genus Esox (Artedij Linnaeus. 



The Pikes. 



Body very elongate; head depressed ; lateral line present ; branch- 

 iostegals 12 to 20; gill rakers short, toothed; gill membranes sepa- 

 rate; most of margin of the upper jaw formed by the maxillary; 

 supplemental maxillary present; some of the teeth on jaws and vomer 

 large and canine-like, a few being hinged; dorsal fin above anal, on 

 posterior part of the body. 



a. Cheeks and opercles entirely scaly; branchiostegals 11 or 12; 

 dorsal rays 12; fewer than no scales in the lateral series. 



vermiculatiis , 296 



aa. Cheeks entirely scaly; lower half of opercle without scales; 



branchiostegals 14 to 16; dorsal rays 14 to 16; about 125 scales 



in the lateral series. lucius. 296 



