Breeding the Nymph. 317 



thus in captivit}- for some time they seem to become 

 ahnost tame, and to watch for their meals. As soon as 

 a shrimp or a worm is dropped into the water the move- 

 ment seems to be communicated to them, or they sight 

 the intruder, and turn their head on one side to watch 

 it in a ver}- knowing" manner, The}- then steahhily 

 approach. The shrimp pcrha])s is still for a moment ; 

 they wait till it begins to move, then out shoots the 

 mask, and the prey is secured, though not alwa\'S at 

 the first shot. If a house-fl\^ is dropped on the surface 

 of the water its struggles soon attract a nymph, which 

 comes up to the surface to fetch it. and in that case 

 the whole process of capture may be easih' observed. 



When the time for emergence is near at hand pieces 

 of stick, with knots or projections to give foothold, must 

 be fastened in an upright position in the fish-globes, or 

 other aquaria, so that the nymphs may be able to leave 

 the water for their final change. It is not easy to 

 secure the sticks in the requisite position in a glass 

 fish-globe ; but the exercise of a little ingenuity will no 

 doubt bring about the required result. Ever}' part must 

 overhang the water, for restless nymphs sometimes fall 

 before they have finally taken up a position for the 

 change. 



At certain intervals the growing nymph will cast its 

 skin, and these casts should be preserved in alcohol 

 or a from 2 to 5 per cent, solution of formalin. In 

 addition skins from which the imagines have emerged 

 should be preserved, either in the solutions just men- 

 tioned, or mounted on pieces of card. In the latter case 

 different specimens should be placed in various positions, 

 so that by the aid of one or other all parts ma}' be 



