814 l^ATUEAL HISTORY OF AQUATIC ANIMALS. 



Sates, having several species, and others again only one or two. Some species are very limited in 

 their range, whUe others are widely distributed. Gambarus aeutus is an illustration of this wide 

 distribution, ranging as it does through a large number of the States from the Great Lakes 

 southward to the Gulf, and from Missouri eastwaird to the Atlantic coast. C. Bartonii ranges 

 frqm Canada to the District of Columbia and Kentucky ; C. obesns, from Illinois to Louisiana, and 

 from Missouri to New York and Virginia. G. affinis occurs in all of the Middle States and in 

 Maryland and the District of Columbia, and G. virilis extends from Lake Winnipeg, British 

 America, to Toronto in the east and Texas in the south. Very many of the species have been 

 recorded from only a single locality each, but this does not necessarily imply a restricted range, 

 as they may occur in other places in which no collections have yet been made. 



Economic value. — Although Americans, as a rule, do not regard the eating of Crayfishes 

 with much favorj these animals are probably used as food in many of the localities in isvhich they 

 are abundant and can be easily obtained. The French in this country are perhaps the principal 

 consumers of this delicacy, as they are in Europe, where their own country can supply only a 

 small part of the demand, great quantities being annually imported into France from Germany 

 and other neighboring countries. » In the United States the principal centers for the consumption 

 of Crayfishes are New York City and New Orleans, and we have been unable to learn of any other 

 cities demanding a regular supply. New Orleans derives its supplies from the fresh waters near 

 at hand, but New York depends upon more distant sources. The Cray-fish season in New York 

 City begins early in the spring and lasts until fall, or until frost sets in. The first supplies come 

 from the Potomac Eiver at Washington, where the Cray-fishfes are first taken soon after the 

 breaking up of the ice in the river. About June 1 the weather becomes almost too warm for 

 the shipment of Cray-fishes from Washington, and another more northern locality, Milwaukee and 

 vicinity, begins to send supplies to New York, In the early part of July, Montreal adds her 

 quota to the New York markets, and the shipments from these two latter localities continue as 

 stated above until into the fall. The Potomac River Cray-fishes are larger than those from 

 Milwaukee, while the Montreal species is the smallest of all. The Milwaukee Cray -fishes are most 

 esteemed by epicures, their flesh being less coarse and of a finer flavor than any of the otheF 

 species sold in the New York markets. The Potomac species is the darkest in color when living, 

 but does not turn red by boiling, while the Milwaukee and Montreal species do. Small quantities 

 of Cray -fish are very probably brought to New York City from the State and from New Jersey, 

 but if 80 they do not pass through the larger markets, arid there is no regular supply. 



The Potomac River Gray-fish sent to New York is the Gambarus affinis Erichsbn, and the 

 Milwaukee species is the Gambarus virilis Hagen. We have never examined specimens of the 

 Montreal species. The New Orleans market Cray-fish is the Gambarus GlarMi Girard, while the 

 San Francisco species, as already stated, is the Astacus higrescens. One of the Lower Mississippi 

 River species, either the Gambarus Glarlcii or the Gambarus aeutus, burrows into and causes much 

 damage to the levees of the river in the vicinity of New Orleans. 



Habits.— Cray -fishes differ widely in their habits, and while some species prefer clear run- 

 ning streams, others live in more quiet waters, and still others upon muddy banks, where they dig 

 holes, and remain much of the time out of the reach of water. 



Dr. C. C. Abbott has given us the following account of the habitS of three of our commoner 

 species of Oray-flshes, which occur near Trenton, New Jersey. > They are Gambarus aeutus, G. 

 affinis, and G, Bartonii, which have already been referred to as living in regions where Cray- 

 fishes are taken as food : / 



'American Naturalist, yii, 1873. 



