RIVER SILVERSIDE. 919 



very elongate, tran'sluoent ; dorsal spines fonr; scales small. This genns contains but 

 a single species, peculiar to tke fresh waters of the Western States — a, small fish, very 

 slender and graoefal, and of delicate organism. 



111. Labiuesthes sicculus Cope. 



River Silverside; Skipjack. 



Chirostoma sicoulum, Cope, Proc. A.cad. Nat. Soi. Phila., 1863, 81. 



Labidesthea sicaulus, Oopb, Proo. Amer. Phil. Soc, 1870, 455. — Jordan, Man. Vert., Ist 

 Ed., 1877, 2d Ed,, 1878, 261. 



Description. — Form very slender, the depth contained 6 to 7 times in length ; the head 

 abont 4i ; eye large and ronnd contained 3^ times in the length of the side of the head, 

 and li times in the length of the snoat ; top of head and mnzzle plane, the latter con- 

 vex transversely, its tip about even with that of the lower jaw ; front with-a median 

 ridge; teeth slender and simple; scales small; in 14 longitadinal and 75 transverse 

 series ; anal fin very long, nearly one- thirds the length of the body; first dorsal short, 

 with 4 very weak spines; D. 1 ; V. 10; A. I, 2J; Ventrals I, 5; color very clear, trans- 

 lucent olive; in life qaite transparent; above dasted with black points ; sides with a 

 very distinct, silvery band, which covers one row and two half rows of scales, edged 

 above with plambeons; cheeks silvery. Length 3 to 4 inches. 



Habitat, Michigan to Tennessee, west to Iowa, Detroit River (Cope), Sandnsky Bay, 

 Clinch Elver (Cope), Cumberland Eiver, Illinois River, Wisconsin River, and in most 

 streams of Ohio and Indiana. 



Diagnosis. — This is the only fish found in Ohio with a long, slender 

 body, two dorsal fins, and a bright, silvery stripe along the sides. 



Habits. — This little creature is one of the most singular and elegant 

 -of our fishes. It occurs in great abundance where found, and is espec- 

 ially numerous in clear pools left in summer by the fall of the waters in 

 the stream which has filled them. It swims near the surface, and often 

 throws itself out of the water, for which reason it is known to Indiana 

 boys by the name of " Skipjack." It is an attractive creature in the 

 aquarium, but from its delicacy of organization hard to keep alive. 



FAMILY XIX. APHEEDODERIDiE. THE PIRATE 



PERCHES. 



Body oblong, moderately compressed, covered with ctenoid scales ; dorsal fin single, 

 high, with but three or four spines, which are rapidly graduated, the first being quite 

 short ; ventral fins thoracic, without distinct spine, and with seven soft rays ; mouth 

 moderate, the lower jaw slightly proj acting, the maxillary reaching to the anterior 

 border of the eye ; teeth in villiform bands, on jiws, vomer and palatines ; pharyngeals 

 narrow, the lower separate, with villiform teeth ; preorbital, preoperole and other bones 

 of the ' head strongly serrated ; branchiostegals six ; gill membranes free from the 

 isthmus; air-bladder simple; pyloric cob sa about twelve; scales moderate, ctenoid; no 



