Native Fishes of Iowa. 165 



7. Lepidosteus platystomus. — Rafinesque. — Short-nosed 



Gar-pike. 



This species is similar to the preceding, but smaller, and 

 less abundant in Iowa. It inhabits the Mississippi valley, and 

 is of no value whatever. 



CCCC ^°^y covered with cycloid scales. A broad triangular plate between 

 the branches of the lower jaw. Air bladder cellular, and used in 

 respiration. A lanceolate appendage under each gill cover. 



Family j. AMIIDiE.— The Bow-fins. 



Genus 7. Ami a. — Z. 



8. Amia calva. — L. — Bow-fin. Mud-fish. Dog-fish. "John 



A. Grindle." 



This species inhabits sluggish waters, lakes and bayous. It 

 is seldom taken in our river currents. If kept moist it will 

 live longer out of water than any of our cat-fishes. The male 

 has a large black spot at base of caudal fin above. It reaches 

 a length of 2^ feet, takes the hook readily, but is worthless 

 for food. Its relations to earlier forms make it of much inter- 

 est to zoologists. Dakota to Texas and east. 



"g"D Tail not evidently heterocercal. Air bladder never cellular and lung- 

 like. 



T) Body naked. Head with 8 barbels. Two dorsal fins, the posterior 



adipose. The anterior rays of first dorsal and pectoral fins devel- 

 oped as a strong spine. 



Family 6. SILURIDiE. — The Cat-fishes. 



d Adipose fin with its posterior margin free. 



e Pre-maxillary band of teeth (teeth of upper jaw) without lateral backward 

 process. 



f Supra-occipital and second inter-spinal bones so meeting as to form a con- 

 tinuous bony bridge from head to first dorsal spine. 



Genus 8. Ictalurus. — Rafinesque. 



Tail forked, species of a silvery color. 



g Anal fin very long, its rays 32 to 35 in number; base of anal fin one-third 

 the length of the body. 



