CHAPTER II. 



THE CRAYFISH. 

 (Astacus torrentium.) 



THE river Crayfish, Astacus torrentium, occurs in many 

 English streams, especially those draining districts with 

 calcareous soil. The species most usually obtained in 

 laboratories is the continental A. fluviatilis, distinguished 

 by the red tips to its claws. The former is abundant in 

 many small streams on the borders of Surrey and Hamp- 

 shire, and is still to be found in some small tributaries of 

 the Thames, though its numbers have not yet recovered 

 from the disease that in 1887 caused great mortality. 

 Previous to this epidemic they were so abundant in the 

 Thames and its tributaries that a regular industry of 

 making crayfish-pots flourished in many places. The pots 

 were baited with any carrion that came handy. A ready 

 market is always obtainable, for when boiled in salt water 

 they form brilliant garnishing to salads and are in flavour 

 little if at all inferior to large prawns. The crayfish most 

 commonly used for culinary purposes on account of its 

 superior flavour and appearance is A. fluviatilis. The 



