THE CANADIAN ENTOMOLOGIST. 201 



slender, which attack the fibrous roots of the corn, and so destroy them 

 that the plants may be pulled up very easily with the hand. After a time 

 the plants begin to wither and the grain fails to mature. In some instinces 

 it is believed that the injury inflicted by this tiny creature would result in 

 the loss of fully one-third of the crop. The perfect beetle is about one- 

 fifth of an inch long, with a width scarcely equal to half its length, and 

 of a pale, dull greenish yellow color without spots or stripes. 



The general alarm which prevailed several years ago in reference to 

 the Colorado Potato Beetle seems now to have to a great extent subsided, 

 and notwithstanding that the insect has been very abundant in some sec- 

 tions, it has not been so generally injurious, and where it has appeared in 

 abundance prompt remedial measures have been successfully employed. 

 It has been claimed, and, I suppose, correctly so, that this pest originally 

 came from the canons in the Rocky Mountains, in the State of Colorado, 

 where it is said to have fed on some wild species of Solanum growing 

 there. It was my privilege during the latter part of August of this year 

 to spend a week in this district, and while there I travelled fully one 

 hundred miles through those canons. Several species of wild Solanum 

 grow in abundance almost everywhere in the adjoining plains as well as in 

 the canons, and every opportunity was embraced of examining them, but 

 in no instance could 1 detect any evidence of the presence of the Colorado 

 Potato Beetle in any of its stages. Besides, I saw several potato patches, 

 and these also seemed quite free from any insect trouble. This seemed 

 to me not a little singular in view of the extremely prolific nature of the 

 insect. Can it be that it has migrated so completely as to leave over large 

 areas no representatives behind, or have its natural enemies so increased 

 as to almost annihilate the pest ? Our farmers here would, I am sure, 

 gladly hail the advent of either of these agencies should it free them from 

 this troublesome insect. 



The question of the use of the most suitable and economical poisons 

 for the destruction of injurious insects still attracts much attention, and 

 Paris Green continues to head the hst as the most generally useful, not- 

 withstanding the efforts which have been made by interested parties to 

 replace it by London Purple. London Purple is an arsenical mixture, a 

 waste product, which accumulates during the manufacture of aniline dyes. 

 Before its introduction as an insect destroyer it had no commercial value; 

 on the contrary, the dye makers were at considerable expense and trouble 

 in getting rid of it as it accumulated. Arsenic, which is the active 



