FIRH OF ONTARIO. 71 



pointed teeth, usually forming a narrow band, boiies of the mandible 

 firmly united ; scales moderate ; gill opening not restricted above, the 

 opercle with its margin not adnate to shoulder girdle ; preopercle, pre- 

 orbital, and mandible with mucous pores; dorsal and anal tins similar, 

 small, or rather large, the dorsal inserted either in front ofy a'bove, or 

 behind, the front of anal ; ventrals well developed ; air bladder .present ; 

 sexes differing in colour, size and development of the tins, the anal fin in 

 the male normal; intestinal canal short; first superior pharyngeal without 

 teeth, second with teeth, third and fourth coossified, with teeth. Species 

 very numerous, mostly American, inhabiting fresh waters and arms of 

 the sea. They are oviparous. 



SiBGEXus FOXTINUS. 



Killif]sh. {Fiuuhdus diaplumu-'<.) 



1/Vv 



\ 



(78) Killifish. Fresh-water Killy. 



(Fundulus diaphanus.) 



Body rather slender; head flat above; mouth very protractile, small, 

 its width somewhat greater than the length of the lower jaw. Fins low, 

 the dorsal midway between the tip of the snout and the root of the caudal. 

 The anal is wholly under the dorsal. Caudal large, convex behind. 



D., 14; A., 12. Scales on lateral line, 46. 



The females are olivaceous, sides silvery, with fifteen to twenty-five 

 narrow dark crossbands ; fins pale. In the breeding season the males are 

 olive with about twenty pearly white cross bars. 



Abundant in bays and shallow inlets near the lakes ; usually found 

 quite close to the shore line, associated in small shoals. A fairly good 

 bait fish, though not as attractive as the bright shiners and chub. 

 ^^This species attains a length of about four inches. 



Order HEMIBRANCHII. (The Half-gills.) 



Interclavicles developed. Gills pectinate. Post-temporal simple, not 

 furcate; supraclavicle quite small. Superior pharyngeal bones reduced in 

 8 F. 



