70 Lessons in Zoology. 



water cousin, it is not at all fastidioas, bat greedily swal- 

 lows frogs, tadpoles, water-snails, — anything and every- 

 thing that comes along. 



A little colon; of crayfiahes can be kept in a cellar of an; cool, 

 dark place, in a tnb vith tvo or three incbes of water and earth, 

 and atones enongh for a false river-bed. The; will show consider- 

 able ingenait; in bailding tic; caves, into which the; beat a head- 

 long retreat when disturbed, and which the; will rebuild as often 

 as we demolish them. Uof ortanatel;, the; are cannibals, and even 

 if well fed with raw meat, show a wicked preference for their own 

 brothers and sisters, that nnmbers the da;s of onr little settlement. 



The dull green or brown color of the crayfish, its 

 smaller size tban the lobster, its similarity in shape, skel- 

 eton, and appendages, and the equal number of append- 

 ages, are all not<?d. 



Fig. 2. 



A preparation of the m»ath-parts npun pasteboard is almost 

 essential in the case of the crayfish, and it will be found well worth 

 the while to glue the carapace and the rings of the abdomen to the 

 center of the card, and then to arrange all the appendages in regu- 

 lar order on either side. 



The division of the telson into two jointed pieces, the 

 variation in the anterior pairs of swimmerets, the differ- 

 ent shape of the rostrum, the lower part of the long an- 

 tennae, and the great claws, should then be observed. 



In stadjing the crab, tiia differences between that and the lobster 

 at first eogross onr attention. 



