HISTORY OF THE FISHES OF MASSACHUSETTS. 131 



GENUS II. HYDRARGYRA, Lacep. 



Upper surface of head flattened ; but the jaws are not depressed. Fine card-like 

 teeth upon the jaws. Opening of mouth semicircular. Lower pharyngeal teeth with 

 rounded crowns, the medio-posterior ones the largest. Branchial rays six on either 

 side. Dorsal opposite to anal, as in the genus Esox. Caudal posteriorly subtruncatecl. 

 Upper surface and sides of head covered with scales. 



Hydra rgyra flavula, Storer. 

 The Basse Fry. 



(Plate XXHI. Fig. 5. Male. C. Female.) 



Esox flavulus, New York Gudgeon, Mitch., Trans. Lit. and Phil. Soc. of N. Y., i. p. 439, pi. 4, fig. 8. 

 Cyprinodon flavulus, Val., in Humboldt and Bonpland, II. p. 164, pi. 62, fig. 3. 

 Hydrargyra flavula, The Basse Fry, Stoker's Report, p. 95. 



" " Atees, Bost. Joura. Nat. Hist., iv. p. 267. 



" " Girakd, in Lit. 



Hydrargyra formosa, Storer, Proc. Bost. Soc. Nat. Hist., i. p. 76. 

 Hydrargyra trifaseiata, Storer, Bost. Journ. Nat. Hist., I. p. 417. 

 Fundulus fasciatus, Striped KUliflsh, Dekat, Report, p. 216, pi. 31, fig. 98. 

 Hydrargyra vernalis, Cov. et Val., Hist. Nat. Poiss., xviii. pp. 206, 207. 

 Hydrargyra flavula, Storer, Mem. Amer. Acad., New Series, II. p. 432. 



" " " Synopsis, p. 180. 



Color. Female of a yellowish-green above, lighter upon the sides, and white be- 

 neath. Several longitudinal, interrupted black bands, sometimes five in number, may 

 be distinctly seen, at other times not more than one or two, upon the sides, extending 

 from the gill-covers almost the whole length of the fish. At the base of the caudal fin, 

 just at the termination of the longitudinal bands, are three or more less distinct 

 transverse bands of a similar color. 



In the male, the sides and back are of a greenish-black ; the sides are crossed by 

 numerous slate-colored, nearly black, transverse bands, varying very much in their 

 number and width in different individuals, — some individuals exhibiting ten or twelve 

 bands only, while in others are observed twenty, or even more. In some specimens 

 these bands are of the same size throughout their whole length ; in others, they 

 diminish gradually from the centre to the sides towards the abdomen, upon which they 

 are lost. In some specimens these bands are less than the sixteenth of an inch wide ; 

 in others, they are quite the eighth of an inch. The lower portion of the sides, as 

 well as the abdomen, is of a beautiful yellowish-green color. The operculum is marked 

 by a large black spot ; the preoperculum is fuliginous, sometimes cupreous. The 

 dorsal fin is violet-colored, with a black spot, circular in some individuals, upon the 



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