ii6 British Dragonjlies. 



of water and carefully sorted, with the assistance of the 

 analytical tables on pp. 40-44. The different species as 

 far as can be ascertained, must be kept separate, and 

 even the individuals of different size, but of the same 

 species, must be treated in the same way, for Dragonfly 

 nymphs have not the slightest hesitation about preying 

 upon their smaller brethren. Indeed, one may even fall 

 a victim to another of its ozvn size just after an ecdysis, 

 while the new skin is soft and its owner helpless. It is 

 clear, therefore, that even those of the same size and 

 kind must not be overcrowded ; but providing a plenti- 

 ful supply of suitable food will go a great way to keep 

 in the background their cannibal instincts. 



With regard to food, the common fresh-water shrimp 

 {Gainmanis fiiiviatilis) seems to be much relished by 

 many of the larger nymphs — the Anisopteridcs. In the 

 spring tadpoles may be given, and to the /Eschnas a 

 tiny red worm always appears a tempting morsel. But 

 most living creatures that are not too large are readily 

 taken. A slender Myriapod once given to a large 

 nymph was, however, quickly rejected with signs of 

 evident dislike. The Zygoptcridcs require smaller 

 provender, and for them water-fleas, or animals of about 

 that size, are suitable ; but they are able to see and take 

 very small creatures, and also, on the other hand, larger 

 ones than would be expected. 



For purposes of study the nymphs may be kept in 

 ordinary fish-globes containing mud and weeds, and a 

 snail or two to keep the glass clean. Dead leaves and 

 bits of stick should also be supplied, for some nymphs 

 like to hide under the former, and others to rest upon 

 the latter. When the larger n}'mphs have been kept 



