INJURIOUS AND BENEFICIAL INSECTS. 239 



dreds of new species. Such an one was Dr. Thaddeus W. 

 Harris, whose leisure moments were consecrated to the bene- 

 fit and advancement of the agricultural interests of our State, 

 and the Commonwealth, perhaps, never made a better invest- 

 ment than in supplying the agricultural community with an 

 illustrated copy of his immortal work. On looking over Dr. 

 Harris's work we find that he mentions about six hundred 

 species as injurious to vegetation, and as others have been 

 added since then, it is not improbable that we have at least 

 one thousand destructive species, i. e. about one-tenth of the 

 entire number (10,000) of insects which undoubtedly are to 

 be found livins: within the limits of this State. As to the 

 losses sustained from their attacks it would be difficult to say 

 how great they are, but it is to be estimated at least by hun- 

 dreds of thousands of dollars. The amount of waste by the 

 agency of insects is really appalling, and even now but slightly 

 appreciated by our farming community. 



We have perhaps little idea how many insects are preying 

 upon our crops and shade and ornamental trees. Perhaps 

 there are, within the limits of our country, one-tenth of the 

 number, i. e. five thousand, given above, which are either at 

 present engaged in the work of injury, or are destined to be, 

 with the o;ro^vth of civilization, which means in this instance 

 the destruction of the natural food of these insects and the 

 substitution of a different diet — our choicest grains and fruits 

 in their stead. 



Durins: the last summer the canker-worm was as destruct- 

 ive as ever, and it seems to have gained a firm foothold 

 among us. It is scarcely creditable that so conspicuous and 

 comparatively easily assailed an insect as this does so much 

 annual damage. It would seem as if the birds did not feed 

 upon it to much extent. We have personally never seen birds 

 feeding upon the canker-worm, though Professor Wyman 

 states that doves eat them sometimes in large numbers. As 

 we have stated in a former report there are certain kinds of 

 caterpillars that birds do not relish. Indeed birds seem to 

 have certain fancies of their own among edible insects. Thus 

 the martin will store up in its nest quarts of the common 

 striped beetle of the potato, to the exclusion of all other 

 insects. 



