212 ZOOLOGY. 



Its nearest representative in the United States is the Salmo fontinalis or 

 connmon brook trout, occurring from Maine to the southern parts of Vir- 

 ginia, and perhaps below this in the mountainous regions. It does not attain 

 a great size in running streams, a weight of four pounds being considered 

 enormous. In small lakes, however, it is found much larger than this, being 

 sometimes mistaken for the Mackinaw or great lake trout, Salmo amethystus 

 of Mitchell. This most gigantic of all Salinonidce inhabits the great lakes 

 of North America, and is especially abundant about Lake Huron. Indi- 

 viduals of 35lbs. weight are of no great rarity, although 15 is perhaps the 

 average. Dr. Mitchell records one weighing 120lbs., but at the present day 

 they seldom exceed 80. Salmo confinis, a less gigantic species, inhabits the 

 smaller lakes of the northern United States : S. siskewit is a native of Lake 

 Superior, and numerous species are found represented in the waters of 

 Arctic America. The genus Tliymallus or greyling, represented in Arctic 

 America by T. vexillifer, is distinguished from the true Salmo by the larger 

 scales and the elongated dorsal. The European greyling is T. vulgaris. 

 Mallotus villosics, or the capelin, is found on the coast of Labrador and 

 Newfoundland, where it is used as a bait for the cod. It is sometimes found 

 in a fossil state, in diluvial formations, on the eastern coast of the United 

 States, as in New Hampshire. The genus Osmei'us, or smelt, is represented 

 by O. viridescens. It is known in some portions of the country as the frost 

 fish, and is exceedingly abundant in the northern United States. In the 

 winter season it congregates in large numbers in Lake Champlain, and may 

 be taken with great ease through holes cut in the ice. Coregonus is 

 another genus of the SalmonidcB, famed for the excellence of its flesh. The 

 celebrated " white fish" of the lakes is included under several species of 

 Coregonus. A species, C. otsego, from the small lakes of New York, is 

 known as the Otsego bass. Additional species occur in the regions north 

 of the United States. Species of this same genus are abundantly distributed 

 over northern Europe. 



ScoPELiD^. Fishes of this family have the upper jaw formed entirely by 

 the intermaxillaries. The branchiostegous rays are ten to fifteen in number. 

 Mouth deeply cleft. A second adipose dorsal. The species are mostly 

 marine, one occurring, however, in the Lake of Mexico, Sau7'us mexicanus. 

 Another genus remarkable for its extreme beauty and diminutive size is 

 Scopelus. 



The Characini are salmonoid fish with a posterior adipose dorsal, and 

 only six or seven branchiostegal rays. The divided air-bladder and tym- 

 panic ossicles ally them to the CyprinidcB. The intestine has numerous 

 coeca, and the superior maxillary enters considerably into the composition 

 of the mouth. Many of them are highly ferocious, and characterize the 

 rivers of South America, where they are sometimes dangerous even to man. 

 The only exceptions to this distribution are to be found in the genus 

 Percopsis of North America, one species of which is found in Lake 

 Superior, another in Lake Champlain, and a third in the Alleghany river. 

 They are highly interesting on account of their palaeontological relations 

 as well as their structure, which combines a ctenoid scale, with a genera] 

 416 



