Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/158

 in which the catfish lives runs north and south it will be found in the southern part of the stream in the winter and in the northern part in summer. This fish is highly prized for edible purposes. In the small streams the catfish is correspondingly small and weighs from less than one pound to two or three pounds only. The small catfish, especially in the small streams tributary to the Ohio and Mississippi, has edible properties which are far superior to the large catfish growing in the rivers themselves.

The catfish of the small streams and lakes are commonly known as bullheads, since the head is large and wide. The name of the most common or best known species is Ameirus nebulosus. This species is found from Maine westward and southward. In Pennsylvania it is known as the Schuylkill cat, and everywhere generally throughout the country as a small catfish.

Codfish.—One of the most famous food fish of the American waters is the codfish. It is a widely distributed fish. There are said to be about 25 genera and 140 species. The codfish is particularly a fish of the northern waters. Only one genus is found in fresh-water lakes and streams.

The Common Cod.—The common codfish (family Gadidæ) is the species Gadus callarias. It is rarely found south of the Virginia coast, but is especially abundant off the New England and Newfoundland coast. The great center of the codfish industry is in the vicinity of Newfoundland. Gloucester, Massachusetts, is the principal town devoted to the codfish industry in the United States. The cod is an omnivorous fish and especially fond of crustaceans, mollusks, and small fish. It also eats vegetation, and it is stated by Jordan and Evermann that all sorts of things have been found in cod stomachs, such as oil cans, finger rings, rubber dolls, rocks, pieces of clothing, etc. The livers of the cod, especially those of Norwegian origin, are extremely valuable, being the source of cod liver oil, which is considered by many to be the most valuable medicinal food known. Cod liver oil, while not palatable, is highly nutritious. The cod livers contain, according to some authorities, over 60 distinct chemical substances, many of which are highly important for their medicinal qualities. The cod move in schools, but not in such dense bodies as the mackerel, herring, and menhaden. Their movements are largely controlled by the temperature of the water and their desire for food. This species probably does not reach a greater length than 3 feet and a weight of more than 25 pounds. The average weight of the large-size cod in New England waters is about 15 pounds and on the Grand Banks of Newfoundland 20 pounds. The average weight of the small-size cod in these waters is about 12 pounds. It is one of the most prolific of fishes. The ovaries of a 21-pound cod were found to contain 2,700,000 eggs and of a 75-pound cod 9,100,000 eggs. The eggs are very small and require about 337,000 to make a quart. The cod is one of the most valuable of all fishes from a commercial point of view and also on account of international re-