HYMENOPTERA. 417 



and others rolling up and dropping off, especially when the 

 bushes are shaken by tiie wind. Having reached the ground, 

 they burrow to the depth of an inch or more in the earth, 

 where each one makes for itself a small oval cell, of grains of 

 earth, cemented with a little gummy silk. Having finished 

 their transformations, and turned to flies, within their cells, 

 they come out of the ground early in August, and lay their 

 eggs for a second brood of young. These, in turn, perform 

 their appointed work of destruction in the autumn ; they then 

 go into the ground, make their earthen cells, remain therein 

 throughout the winter, and appear, in the winged form, in the 

 following spring and summer. 



During several years past, these pernicious vermin have in- 

 fested the rose-bushes in the vicinity of Boston, and have 

 proved so injurious to them, as to have excited the attention 

 of the Massachusetts Horticultural Society, by whom a pre- 

 mium of one hundred dollars, for the most successful mode of 

 destroying these insects, was offered, in the summer of 1840. 

 In the year 1832, I first observed them in gardens in Cam- 

 bridge, and then made myself acquainted with their trans- 

 formations. At that time they had not reached Milton, my 

 former place of residence, and they did not appear in that place 

 till six or seven years later. They now seem to be gradu- 

 ally extending in all directions, and an eflectual method for 

 preserving our roses from their attacks has become very 

 desirable to all persons who set any value on this beautiful 

 ornament of our gardens and shrubberies. Showering or 

 syringing the bushes with a liquor, made by mixing with water 

 the juice expressed from tobacco by tobacconists, has been 

 recommended ; but some caution is necessary in making this 

 mixture of a proper strength, for if too strong it is injurious to 

 plants ; and the experiment does not seem, as yet, to have 

 been conducted with sufficient care to insure safety and suc- 

 cess. Dusting lime over the plants when wet with dew has 

 been tried, and found of some use ; but this and all other 

 remedies will probably yield in efficacy to Mr. Haggerston's 

 mixture of whale-oil soap and water, in the proportion of tw^o 

 pounds of the soap to fifteen gallons of water. Particular 

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