306 INSECTS AT HOME. 



dead ; indeed, if not in a ring before, he almost always rolls 

 himself into one when touched. 



' When the Nigger has reached his full size — a period de- 

 pending on the temperature of the weather and the supply of 

 food, but averaging twenty days — he burrows in the earth, 

 and there makes a little oval house, just big enough for liis 

 body, which has all at once become shorter and thicker : he 

 then plasters the walls of this place with a sort of sticky varnish 

 or glue, which he discharges at this time only ; he keeps on 

 discharging and spreading this glue till he is quite siuTounded 

 with a strong, tough, and hard cocoon, the particles of earth 

 being mixed with the glue, and the whole forming an admirable 

 and perfect defence against wet or the attacks of insects. The 

 period of his stay in this cocoon varies according to circum- 

 stances : if the weather is hot, it sometimes happens that the 

 grub becomes a mummy-like chrysalis in ten days, and a 

 perfect fly, and again on the wing, in five more ; but the 

 greater part of the brood remain unchanged all through the 

 autumn, winter, and spring. I have turned up the cocoons, 

 and found the grub little altered even in May. 



' Soon after this the change to a chrysalis must take place, 

 and the change to a fly occurs, in average seasons, about the 

 middle of July ; when this is accomplished, it moistens one 

 end of its cocoon, so as to make it easy to come out, and then 

 it climbs up through the earth and takes wing. But the 

 plough and harrow, the operations of which are sure to follow 

 the eating ofl" of the turnip-crop, often turn up and expose the 

 cocoons, so that, instead of being an inch or two below the 

 surface, they are laid at the top. Tlie system of crop rotation, 

 however, serves to remove the fly of the Nigger from the food 

 best fitted for its progeny ; and it often happens that the flies 

 come to maturity in a field of ripening grain, the ears of which 

 they mount, and, spreading their wings, float off in myriads to 

 the nearest turnip-field. 



' I find a hundred recipes for the destruction of these 

 Niggers, all of which are moonshine except one, and this, for a 

 wonder, is rational. It is this : buy an immense number of 

 ducks, and turn them into your turnips, and they will devour 

 the niggers by millions, and in a few days become as fat 3« 

 butter. Thus two birds are killed with one stone — the ducks 

 fattened and the turnips saved. 



