212 ZOOLOGY. 
Its nearest representative in the United States is the Salmo fontinalis or 
common 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 Salmonide 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 120\bs., 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 Thymallus 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 villosus, 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 Osmerus, 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 Salmonide, 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. 
Scopenmw#. 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, Saurus mexicanus. 
Another genus remarkable for its extreme beauty and diminutive size is 
Scopelus. 
The Cuaracini 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 Cyprinide. The intestine has numerous 
cceca, 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 paleontological relations 
as well as their structure, which combines a ctenoid scale, with a general 
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