GASTEROSTEID^. XCVIII. 249 



depth nearly 4 ; spines rather low; ventral spine about 

 equal to eye; color olivaceous, marbled with darker; 

 males in spring jet black, finely punctate; D. Ill to 

 V I, 10; A. I, 10; length %$ inches. Ohio to Minne 

 sota and Kansas, chiefly northward; abundant in sluggish 

 streams; an interesting species, remarkable for its pug 

 nacity and for its nest-building habits. 



Var. pygmcea, ( Agassiz ) Jordan. L. SUPERIOR 

 STICKLEBACK. Depth 3f in length; head 3J; caudal 

 peduncle short and stout; body shorter and deeper than 

 the preceding; vent much nearer tip of caudal than 

 snout; color similar; D. Ill or IV I, 6; A. I, 6. L. 

 Superior. 



Var. cayuga, Jordan. CAYUGA LAKE STICKLEBACK. 

 Head 3^ in length; depth 4^; spines all high; caudal 

 peduncle slender; vent much nearer snout than tip of 

 caudal; D. IV I, 10; A. 1, 10. Cayuga L., N. Y., 

 dredged in deep water ( Wilder). Probably this and the 

 preceding are varieties of the variable E. inconstans. 

 Length 1^ inches. 



4. PYGOSTEUS, Brevoort. MANY-SPINED STICKLEBACK. 



1. P. occidentalis, (C. & V.) Brevoort. TEN-SPINED 

 STICKLEBACK. Coastwise, abundant; sometimes ascend 

 ing streams. 



2. P. nebulosus, (Ag.) Jordan. MANY-SPINED LAKE 

 STICKLEBACK. Head 3^ in length; ventral spine long; 

 caudal keeled; sides not mailed; D. IX 10; A. I, 8. 

 Great Lakes (scarcely distinct from preceding.) 



3. P. mainensis, (Storer) Brev. MAINE STICKLEBACK. 

 Sides with a serrated plate ; body banded; D. VII I, 9 ; 

 A. I, 8. Kennebec R., Maine. 



