CYPRINODONTID^E. XXXVII. 85 



of back ; a black spot on D. ; lower fins sometimes yellow, and top 

 of head black; 9 much larger than g, paler, a black band on 

 level of eye with two shorter bands below it; one or two black 

 cross-bars at base of C. Head 3f ; depth 4. D. 12. A. 10. Scales 

 36-13. L. 6. Cape Cod to Fla.; the largest of the genus, common 

 in shallow bays. S. occurs F. similis Baird & Girard, with scales 

 33, and both sexes resembling <J of F. majalis. (Lat., pertaining 

 to May.) 



bb. Branchiostegals 5 : <f with silvery spots and bars ; 9 nearly plain oliva- 

 ceous; young with black cross-bars. 



202. F. heteroclitus (Linnams). COMMON KILLIFISH. MUM- 

 MICHOG. MUD-FISH. Body short, deep, the head short, broad ; 

 eye about equal to snout ; dark green, sometimes orange below, 

 sides with scattered yellowish spots, sometimes running into silvery 

 cross-bars ; vertical fins dark, with pale spots, usually a black spot 

 on D.; young $ with 9 or 10 silvery bars; young 9 with 9 or 10 

 black bars; adult 9 nearly plain. Head 3|; depth 3^. D. 11. 

 A. 10. Scales 35-12. L. 2 to 5. Maine to Mexico; everywhere 

 common along shore, in shallow water; S. specimens (var. grandis 

 Baird & Girard) larger and brighter. (F. pisculentus Mitchill; 

 F. nigrofasciatus Le Sueur.) (erepos, different; K\ITVS, slope.) 



act. Scales moderate, 43 to 50 in longitudinal series. 



c. Dorsal inserted before A. ; sides with many dark cross-bands. 



203. P. diaphanus (Le Sueur). Body rather slender; head 

 slender, flat above; fins low. Olivaceous, sides silvery, with 15 to 

 25 narrow dark cross-bands ; fins nearly plain. Western specimens, 

 var. menona Jordan & Copeland (Ohio, W.) have the bands very 

 distinct, and somewhat irregular ; the back always spotted ; some- 

 times silvery cross-bands replace the darker. E. specimens (Cay- 

 uga L., N. Y. Bay) have the back plain, the bands faint and 

 regular. Head 3^ to 4 ; depth 5. D. 13. A. 11. Scales 46-12. 

 L. 4. Great Lakes and tributaries, E. to coast of Mass., S. to N". 

 Ind., W. to Colorado, ascending clear streams to their sources, also 

 in lakes and river mouths. 



cc. D. inserted over front of A. ; sides with regular series of orange or 

 brown spots. 



204. F. catenatus (Storer). STUD-FISH. Body long, com- 

 pressed ; head broad ; color greenish ; $ with an orange spot on 

 each scale, 9 with smaller brown spots, these forming continuous 

 stripes. Head 4; depth 4. D. 14. A. 15. L. 7. Mountain 

 streams, E. Tenn. and Ozark region; very pretty. In Alabama 

 R. is a still brighter species (F. stellifer Jordan), with scattered 

 orange spots. (Lat., with chain-like lines.) 



aaa. Scales very small, about 60 in a longitudinal series ; sides barred. 



