Family AMIIDAE 



THE BOWFIN FAMILY 



The bowfins are primitive fishes with stout bodies covered with heavy, 

 smooth scales. The head is covered with smooth plates. The mouth is 

 horizontal and rather large. The jaws have two kinds of teeth: the larger 

 and outer are conical; the vomer, palatines, and pterygoids bear small 

 teeth. Only one genus and one species are known in North America 

 today. Fossil forms are known outside of North America. 



GENUS Amia Linnaeus 



The characters of the genus are found in the following description of 

 its one species. 



BOWFIN (Fresh-water Dogfish) 

 Amia calva Linnaeus 



The bowfin (Figures 5 and 6) is a relic of an ancient family of which 

 only one species remains today. It has a rather primitive skeleton, 

 partly of bone and partly of cartilage. The head is covered by thin, bony 

 plates. The dorsal fin is very long and 'low, reaching almost to the tail. 

 The tail is rounded and of a modified heterocercal type. The body, which 

 is rather stout, is covered by large, cycloid scales. The back and sides 

 are an olive or a brownish green, and the belly is white. The dogfish has 

 a pair of short nasal barbels. The male is distinctly marked by an 

 ocellus, or eye spot, at the base of the caudal fin (Figure 5) . The swim 

 bladder is bifid in front and connected with the pharynx and may be 

 used as a lung. The dogfish reaches a length of over 2 feet and a weight 

 of 10 pounds. 



Bowfin are very common in the Mississippi River and all its tribu- 

 taries. They range eastward in the Great Lakes drainage, exclusive of 

 Lake Superior, to Vermont and southward to Florida and Texas. They 

 are found in some lakes of northern Minnesota and in almost every 

 important lake of southern and central Minnesota. Some confusion 

 in the northern distribution of this species has been caused by reports 

 of dogfish in some of the boundary lakes, such as Lake of the Woods. 

 Apparently this is due to the local application of the name dogfish to 

 the burbot {Lota lota maculosa) . Ainia calva is apparently absent 

 from Lake of the Woods and its connected waters (Hubbs, 1945) . 

 Greene (1935) reported them from many localities in Wisconsin. 



They prefer sluggish water and often come to the surface to gulp 

 in air. Dogfish kept in aquaria at the University of Minnesota come 

 to the surface every few minutes, expelling air from the swim bladder 



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