Potato Culture. 



potato-bug, (coryphora juncta, Ger- 

 mor,) which has existed throughout 

 a great part of the United States from 

 time immemorial. This latter insect, 

 however, feeds almost exclusively on 

 the horse-nettle, (Solarium carolinense, 

 Linn.,) and is never known to injure 

 the potato. Both insects are figured, 

 so that one need not be mistaken for 

 the other. 



Figure 14, b, b, b, gives a view of 

 the larva of the true Colorado potato- 

 bug, in various positions and stages 

 of its existence. Figure 15, b, b, of 

 that of the bogus Colorado potato- 

 bug. It will be seen at once that the 

 head of the former is black, and the 

 first joint behind the head is pale and 

 edged with black behind only that 

 there is a double row of black spots 

 along the side of the body ; and that 

 the legs are black. In the other larva, 

 (Fig. 15, It,) on the contrary, the 

 head is of a pale color, the first joint 

 behind the head is tinged with dusk 

 and edged all round with black ; there 

 is but a single row of spots along the 

 side of the body, and the legs are 

 pale. 



Figure 14, d, d, exhibits the true 

 Colorado potato-bug ; Figure 15, the 

 bogus Colorado potato-bug; each of 

 its natural size. Figure 14, <?, shows 

 the left wing-case enlarged, and Fig- 

 ure 15, e, an enlarged leg of the latter. 

 On a close inspection, it will be per- 

 ceived that in the former (Fig. 14, 

 e) the boundary of each dark stripe 

 on the wing-cases toward the middle 

 is studded with confused and irregu- 

 lar punctures, partly inside and part- 

 ly outside the edge of the dark stripe ; 

 that it is the third and fourth dark 

 stripes, counting from the outside, that 

 are united behind, and that both the 

 knees and feet are black. 



In Figure 15, d, on the contrary, it 

 is the second and third stripes not 

 the third and fourth counting from 

 the outside, that are united behind, 



and the leg is entirely pale, except 

 a black spot on the middle of the 

 front of the thigh. The eggs (Fig. 

 14, a, a, and Fig. 15, </, d) are yel- 

 low, and are always laid on the under 

 side of the leaf in patches of from 

 twenty to thirty; those of the bogus 

 are of a lighter color. Each female 

 of the true Colorado potato-bug lays, 

 according to Dr. Schirmer, about se- 

 ven hundred eggs. In about six days 

 the eggs hatch into larvae, which feed 

 on the foliage of the potato plant 

 about seventeen days ; they then 

 descend to the ground, where they 

 j change into pupae at the surface of 

 I the earth. The perfect beetle ap- 

 pears about ten to fourteen days after 

 the pupa is formed, begins to pair in 

 about seven days, and on the four- 

 teenth day begins to deposit her eggs. 

 There are three broods of this insect 

 every year. Neither geese, ducks, 

 turkeys, nor barn-yard fowl will touch 

 the larva of the Colorado potato-bug 

 when it is offered to them, and there 

 are numerous authentic cases on re- 

 cord where persons who have scald- 

 ed to death quantities of these larvae, 

 and inhaled the fumes of their bodies, 

 have been taken seriously ill, and even 

 been confined to their beds for many 

 days in consequence. It is also re- 

 ported to have produced poisonous 

 effects on several persons who han- 

 dled them incautiously with naked 

 hands. Various plans have been 

 tried to destroy this persistent enemy 

 of the potato plant. Powdered helle- 

 bore is said to have been used with 

 effect as a means of destroying the 

 pest. It should be dusted on and 

 under the foliage when the plant is 

 wet with dew. Hellebore, however, 

 is a dangerous remedy on account of 

 its poisonous qualities. A mixture 

 of one part salt, ten parts soap, and 

 twenty parts water, applied to every 

 part of the plants with a syringe, is 

 quite effectual. Several cannibal and 



