PODOPHTHALMIA. 



53 



individuals of the genus Oambarus. Many of our species, which have been described 

 by Dr. Hagen, have burrowing habits, and are thus productive of considerable damage 

 in mill-dams, and especially in the levees of the Mississippi. In Europe the crayfish 

 are extensively used for food, as they are to a certain extent in our Southwestern 

 States. In France there are several large farms for their propagation and cultivation, 

 and when desired for the market they are captured by sinking in the water bundles of 

 brushwood, in which the individuals become entangled and are brought to the sur- 

 face. An interesting form is Camharus 

 pelhicidus, the blind crawfish of Mammoth 

 Cave and the neighboi-ing caverns of Ken- 

 tucky and Indiana. In these forms the eye- 

 stalks remain, but the optical portions have 

 almost entirely disappeared, — a good ex- 

 ample of the effects of disuse, for in the total 

 darkness of the subterranean streams the 

 use of an organ of vision would be ex- 

 tremely slight. Dr. Packard has recently 

 described a fossil crawfish from the Tertiary 

 of our Western States. 



To the New Englander the lobster is 

 by far the most important member of the 

 whole class of Crustacea. The genus Moma- 

 rus, to which it belongs, contains three spe- 

 cies, vulgaris of Europe, capensis from the 

 Cape of Good Hope, and the americanus 

 ranging from Labrador to New Jersey, and 

 possibly even further south. Dr. Coues hav- 

 ing found a single specimen near Beaufort, 

 N.C. It frequents rocky bottoms, hiding 

 among the stones, or occasionally varying 

 its habitat for sandy or gravelly regions. 

 Lobsters are very fond of decaying animal 

 matter, and the nets and traps employed 

 in capturing them are usually baited with 

 fish offal. Two methods of lobster fish- 

 ing are in vogue. In one a large net, with the bait fastened in the centre, is 

 lowered to the bottom, and after a sufficient time is hauled to the surface so 

 rapidly that the lobsters have no chance to escape. The more usual means of 

 catching these animals is by "lobster-pots." These are wooden frames usually 

 constructed of laths with netting ends. In one or both ends is a small circular 

 opening, through which the lobster passes to reach the bait on the inside of the 

 pot. These pots are sunk in promising spotfe, their position being marked by a wooden 

 float. Weather permitting, the pots are visited every day and hauled to the surface by 

 means of the rope connecting the float to the pot. Frequently, when the character of 

 the bottom permits, the pots are attached together in trawls, each end of the trawl line 

 being marked by a float. The number of pots set by each fisherman varies, few using 

 as many as one hundred. Possibly the average may be forty or fifty. 



The lobster industry is very large, and we gather from the pages of Mr. Rath- 



FlG. 63. 



- Cambamis pellucidus, blind crawfish of 

 Mammoth Cave, natural size. 



