SYSTEMATIC CATALOGUE OF FISHES. 145 



The species reaches a maximum length of 5 feet, and thus rivals the Great Lakes 

 muskallunge (Esox masquinongy) with which it has until recently been identified. 



Family PCECILIID^. ' The Mummichogs, Top Minnows, etc. 



A numerous family of small fresh-water, brackish-water, or salt-water fishes 

 found in all parts of the world, with many representatives in the United States. 

 They are of no value as food, but are of great importance as food for other fishes. 

 The sexes are usually dissimilar in form and size, and many of the species bring 

 forth their young alive. The principal characters of the family are: Elongate 

 body, compressed posteriorly, flattened anteriorly, covered with large cycloid 

 scales; no lateral line; mouth terminal, premaxillary bones protractile and form- 

 ing the margin of the upper jaw; jaws provided with cutting or villiform teeth; 

 branchial membranes united, free from the isthnms; gill-rakers short and thick; 

 pseudobranchise absent; dorsal fin single, composed only of soft rays and placed 

 posteriorly; caudal fin square or concave, not forked; ventral fins abdominal; 

 pectoral fins inserted close together. Of the 20 or more American genera 5 are 

 represented in North Carolina by 9 species. 



Key to the North Carolina genera of killi-fishes. 



i. Lower jaw strong and projecting; intestine comparatively short, with few convolutions; 

 teeth slightly movable. 

 a. Anal fins similar in both sexes; species oviparous. 



h. Teeth pointed (none compressed, tricuspid, or bicuspid). 



c. Teeth in bands or in more than one series; dorsal fin placed either before or behind 



anal; air-bladder well developed Fundulus. 



cc. Teeth in a single series; dorsal fin placed anterior to anal Lucania. 



66. Teeth incisors, tricuspid, in a single row Cyprinodon. 



aa. Anal fin in male modified into a sword-shaped organ; teeth pointed, in bands; species 



viviparous Gambusia. 



u. Lower jaw short and weak; intestine long, much convoluted; teeth freely movable, pointed, 

 and in a single series; species viviparous: Heterandria. 



Genus FUNDULUS Lacgpfede. Killi-fishes; Mummichogs. 

 This genus includes some of the best known and most abundant of our 

 "minnows", and has numerous members in all parts of the country, 5 being in 

 the local fauna. Form elongate, posteriorly compressed, and back little or not 

 at all elevated; mouth terminal, lower jaw projecting and rather heavy; a narrow 

 band of teeth in each jaw; fins variable; dorsal origin in advance of, above, or 

 behind anal origin; anal fin larger in male; caudal margin straight or rounded; 

 sexes dissimilar in size, color, etc. Several species abound in water of all degrees 

 of density, while others are confined strictly to either fresh or salt water. Some 

 live on muddy bottom and feed on mud; others swim freely in creeks, rivers, and 

 bays, and subsist largely on insects. All the species go in schools, which some- 

 times contain thousands of individuals. 



Key to the North Carolina species of Fundulus. 



i. Dorsal fin inserted in advance of anal. 

 a. Scales large, less than 40 in lateral series. 

 b. Form elongate; branchiostegals 6; females with several black horizontal stripes, males 

 with numerous black vertical bars majalis. 



