THE AMERICAN ENTOMOLOGIST. 



79 



burst foi'th, destined to couple together, and by 

 laying fresh eggs in other cheese produce suc- 

 cessive generations in the same unvarying cycle 

 of changes. As with House-flies and Meat-flies, 

 the breed is propagated from year to year by a 

 few fortunate individuals securing in the fly 

 state some uncommonly snug and secure place 

 by way of winter-quarters, the great majority 

 of the last autumnal brood falling victims to 

 their various cannibal foes or to the inclemency 

 of the weather. Hence we see at once why all 

 these insects are far less numerous in the early 

 part of the summer, than they are towards the 

 autumn; for being all of them many-brooded, 

 and laying a very large number of eggs, the 

 breed of them naturally, under favorable con- 

 ditions of warmth, increases in a fearfully 

 j-apid geometrical progression as the summer 

 advances. 



We have said that the Cheese-fly breeds exclu- 

 sively in cheese, because that is the only sub- 

 stance in which the larva is at present known 

 to occur. But of course, before man became 

 so civilized as to take to manufacturing cheese, 

 it must have inhabited some analogous sub- 

 stance — a peculiar kind of fungus for example — 

 which perhaps existed only in very small quan- 

 tities and was scattered widely over a large ex- 

 tent of country. Uence, under such circum- 

 stances as these, it was probably, like many 

 other such flies, only to be met with in very 

 small numbers. It is the manufacturing cheese 

 in great quantities, and especially the concen- 

 trating the cheese in a few localities, instead of 

 scattering it broadcast over the whole country, 

 that afibrds such facilities for the great multi- 

 plication of the species. But as we have enlarged 

 more fully upon this last point in our Article on 

 the Increase of Noxious Insects, we need not 

 dwell upon it here.] 



THE HARLEQUIN CABBA«E-BU«. 



{Sfrachia hidrionica. Ilalin) 



y 



Cabbage-growers in the North arc apt to 

 think, that the plant which they cultivate is 

 about as badly infested by insects as it is pos- 

 sible for any crop to be, without being utterly 

 exterminated. No sooner are the young cab- 

 bages above ground in the seed-bed, than they 

 are often attacked by several species of Flea- 

 beetles, one of which, the Wavy-striped Flea- 

 beetle, we figured and illustrated in all its 

 stages in the 8th number of our First "Volume 

 (pp. 158-9). By these jumping little pests the 

 seed-leaves are frequently riddled so full of 



holes that the life of the plant is destroyed ; and 

 they do not confine themselves to the seed- 

 leaves, but prey to a considerable extent also 

 upon the young rough leaves. After the plants 

 are set out, the larva of the very same insect is 

 found upon the roots, in the form of a tiny 

 elongate six-legged worm. Through the oper- 

 ations of this subterranean foe, the young cab- 

 bages, especially in hot dry weather, often 

 wither away and die ; and even if they escape 

 this infliction, there is a whole host of cut- 

 worms ready to destroy them with a few snaps 

 of their powerful jaws; and the common White 

 Grub, as we know by experience, will often do 

 the very same thing. Suppose the unfortu- 

 nate vegetable escapes all these dangers of 

 the earlier period of its existence. At a more 

 advanced stage in its life, the stem is burrowed 

 into by the maggot of the Cabbage Fly (Antho- 

 myia brassicm) — the sap is pumped out of the 

 leaves in streams by myriads of minute Plant- 

 lice covered with a whitish dust (Aphis bras- 

 sicce) — and the leaves themselves are riddled 

 full of holes by the tiny larva of the Cabbage , 

 Tinea {Plutella cruciferurum), or devoured 

 bodily by the large fleshy larvic of several dif- 

 ferent Owlet-moths.* Nor is this the end of 

 the chapter. The Cabbage-fly, the Cabbage- 

 plantlouse, and the Cabbage Tinea were long 

 ago imported into this country from Europe. 

 There is a still more savage foe to the cabbage, 

 that is just beginning to make his way among 

 us from his native home on the other side of 

 the Atlantic. One of the White Butterflies 

 (Pieris rapa;, see Figures t« and 50 in this 

 number) that in Europe are such a plague to 

 the Cabbage grower was introduced acciden- 

 tally into Canada some six or eight years ago ; 

 and already it is spreading into the United 

 States in all directions with giant strides, hav- 

 ing up to this date occupied and possessed the 

 more northerly parts of New England, and as 

 we learn from Dr. Hoy of Milwaukee, Wiscon- 

 sin, being now tolerably common in his neigh- 

 borhood. 



[Fife'..'*.] 



Colors— Shining black ami bright jflluw. 



Severe as are these inflictions upon the North- 

 ern Cabbage-grower, there is an insect found in 

 the Southern States that appears to be, if pos- 

 sible, still worse. This is the Harlequin Cab- 



• yiamcstra picta, Plusia precationin, another Plmia, und 

 two or three difTerent Agrotidiam. 



