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its back, aud by its smaller size. Some of tlie cautbaricles, {Epicauta 

 vitfaia and Jemniscata are also sometimes confounded with the Colorado 

 beetle, by farmers, aud, although they are striped in a similar manner 

 on. their wing-corers, they may be known by their much narrower aud 

 elongate form aud narrow thorax. The Colorado bugs are partial to 

 certain varieties of potatoes, such a.& the Mercer, Shaker, Pinkeye, &c., 

 avoiding as much as possible the Peachblow, Early Kose, Peerless, and 

 Chili, &c., when other varieties are to be obtained. 



As a remedy, Professor Yerrill recommends Paris green, mixed with 

 eight to twelve parts of wheat flour, or with three parts of wood ashes, 

 to be dusted over the i^lanls when wet with dew ; he, however, prudently 

 adds, "It maybe questioned whether it is safe or advisable to mix 

 dangerous mineral poisons with the soil, for the arsenic and copper will 

 remain in the earth, or may be absorbed by growing vegetables, or 

 cause mischief in other ways." The American Entomologist also states 

 that -'Paris green (arsenite of copper) is a slow but dangerous poison; 

 and when dusting x>lauts with it the greatest care should be exercised, 

 so that the wind may not carry it toward the person of the operator, 

 and it may injure the soil if used repeatedly." In jiroof of this, peas 

 j)lanted at the Department of Agriculture, in soil mixed with Paris 

 green rotted immediate!}^ and would not germinate, while those in 

 unadulterated soil grew finely and flourished, but died immediately 

 when transplanted into the soil mixed with Paris green. This danger- 

 ous remedy has already been used to such an extent that in an 

 entomological paper it is stated that 1,200 pounds has been sold in one 

 season at La Crosse, Wisconsin, for the destruction of these potato-bugs. 

 Professor Cook, of Michigan Agricultural College, reports that some of 

 their potato vines and egg-plants were totally ruined by a too free use 

 of Paris green, mixed in the proportion of one part of the mineral to 

 five parts of flour. Mr. H. H. McAfee, superintendent of the experi- 

 ^mental farm of the University of Wisconsin, disapproves of the use of 

 Paris green, on account of its iioisonous i^roperties, and recommends haud- 

 incking and destroying the beetles when they first appear ; he also 

 states that the potatoes are often watery, rank, and of a bad flavor 

 where the Paris green has been used. Mr. Eiley says, " Watch for and 

 destroy early beetles, aud ensnare as mauy as you can by making small 

 heaps of potatoes in the field planted; to these the beetles will be 

 attracted for food, and may readily be killed in the morning." Paris 

 green, (Scheele's green,) he states, if used too abundantly, will kill the 

 vines, and recommends it to be used with six to twelve parts of flour, ashes, 

 plaster, or slaked lime. He also says it is highly improbable that any 

 substance sprinkled either on the vines or on the ground will ever 

 accompany to the table a vegetable that develops under ground, or, in 

 other words, that the arsenic cannot' be absorbed by the plant, to render 

 the root in some degree poisonous. The Canadian Entomologist also 

 recommends Paris green, mixed with flour, ashes, or air-slaked lime, 

 but states that flour is much the best when mixed in the proportion of 

 one part of Paris green, by weight, to ten or twelve parts of flour, dusted 

 over the plants when the dew is on the foliage, from au ordinary flour- 

 dredge. Three pounds of Paris green to thirty or thirty-six parts of flour 

 is suflicient for an acre of potatoes. It also states that it is not danger- 

 ous if carefully used. 



Several substitutes for Paris green are also mentioned, among them 

 arsenic itself, (arsenious acid,) which may be used in the proportion of 

 one ounce to a pound of flour, but it should be colored black with char- 

 €oal or some other coloring matter, to lessen risk of accident from use. 



