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salids remaining in the kernels. The next June, a swarm of moths appeared in the jar, in which they continued to propagate three years, successively, producing moths in considerable quantities in June and in August, with a smaller number at various intermediate times, except during the depth of winter.
These corn-moths, as already stated, were rather larger than those from the wheat, the wings of some of them expanding nearly six tenths of an inch.* The head is smooth and not tufted. The antennæ are threadlike, with distinctly marked joints. The feelers are long and curved upwards; the terminal joint naked, acute, and blackish near the tip; the second or middle joint rather shorter and thicker, hairy beneath, and blackish on the outer side; the basal joint very short and hairy. The tongue makes several spiral turns, and, when extended, is about half the length of the antennæ. The body and fore wings are of that tint of pale brownish gray, which the French call coffee and milk color, and they have the lustre of satin. The fore wings are long and narrow, and are pointed at the end; together with their wide fringes, they are more or less sprinkled with blackish dots, especially near the tips. The hind wings are blackish, with a leaden lustre; they are narrow, and are very suddenly and obliquely contracted to a point at the tips; they are entirely surrounded with a blackish fringe, which is wider on the inner margin than the wing itself. They are folded lengthwise, when at rest, beneath the upper wings. The fore legs are blackish, and the hindmost legs are fringed with long hairs on the inner side. The chrysalis is obtuse at each end; the tail surrounded with a few minute points, three of which are larger than the rest; the rings of the body are smooth, or not notched; and the wing-cases extend nearly to the hinder extremity. The chrysalis-skin generally remains within the grain when the moth comes out; in some few cases, however, it was found sticking out of the orifice in the
* Mr. Curtis, probably through inadvertence, has stated that Butalis cerealella “expands rather more than one inch.” Half an inch is the true measure. See Journal of the Royal Agricultural Society of England, Vol. VII., p. 86. Compare Duponchel, Hist. Nat. des Lépidoptères de France. Supplement. Tome IV., pl. 85, fig. 3.
kernel, and sometimes in the crevices between the kernels. The foregoing minute description, which is taken from perfectly fresh and uninjured specimens, will serve to remove any doubt as to the genus and species to which this corn-moth is to be referred.
It has been proved by experience that the ravages of the two kinds of grain-moths, whose history has been now given, can be effectually checked by drying the damaged grain in an oven or kiln; and that a heat of one hundred and sixty-seven degrees, by Fahrenheit's thermometer, continued during twelve hours, will kill the insects in all their forms. Indeed the heat may be reduced to one hundred and four degrees, with the same effect, but the grain must then be exposed to it for the space of two days. Insect-mills, somewhat like coffee-roasters on a large scale, have been invented in France, for the purpose of heating and agitating the infested wheat, by which the eggs and larvæ of the little corn-moth, or Butalis, are destroyed. Fumigation, in close vessels, with the gas of burning charcoal, is found to be an effectual remedy; and Dr. Herpin states that this process neither imparts any bad flavor to the grain, nor does it impair its power of vegetating. He recommends also the early threshing and winnowing of wheat, as tending to preserve it.* This, indeed, is advocated by the most experienced wheat cultivators in this country, particularly if done by machinery; and it should not be deferred later than the end of July. The concussion and agitation undergone by the wheat in being threshed and winnowed, as intimated by Dr. Herpin, Mr. Judah, and others, is supposed to dislodge the eggs and kill the larvæ of the insect. With the same view, Mr. Owen recommends passing the new wheat through “a rubbing mill, such as is used in Virginia and other large wheat growing districts, to ensure first-rate flour;" after which the wheat may be kept in bulk, or may be immediately ground. If a large surface of grain be exposed in the barn, the granary, or the mill, during the season of the moth, it will assuredly become affected; for, in the night, when these insects are most active and on the wing, they will light upon the exposed surface and deposit their eggs, which, in a few months of hot weather, will produce numerous and successive broods of moth-worms. To secure it from attack, therefore, the grain should be deposited in tight bins or casks, after having been properly prepared by being dried in a kiln, or even by exposure to the heat of the sun. Some persons have succeeded perfectly in preserving grain from the corn-weevil and from the corn-moth by putting it into casks, heated and fumigated with burning charcoal. The charcoal may be burnt in a portable furnace, lowered into the cask by a chain; and the grain should be poured in while the cask is hot. It has been observed that a low. temperature checks the propagation of the corn-moth, and that the larvæ, or moth-worms, in the grain, cannot survive the winter in those places where the thermometer falls to zero. Hence, in the cool and well-ventilated corn-barns of New England, grain will ordinarily be exempt from attack. During the summer, however, grain that has been brought from infected districts, or that has otherwise become contaminated, will be likely to suffer to some extent, even here. From these facts we learn how important it is that wheat and corn, which are to be kept over winter, for use, for sale, or for seed, should be previously well prepared, and should be deposited in suitable vessels in cool apartments, no matter how cold, provid they are also dry. It has been observed that very little corn is attacked in the field, the husks or shucks protecting it from the moths, which find only a few ears, whose ends protrude beyond the husks, whereon to deposit their eggs. Hence some persons recommend keeping corn in the husks, to preserve it from the corn-moth and also from the corn-weevil. This method is objectionable on account of the trouble it occasions, and the increased bulk of the corn; and it is less sure than the means above described.
* See Duponchel. Lépidopt. de France. Supplem. Tome IV., pp. 450-453 ; and Mr. Curtis's paper in the Journ. Royal Society of Agricult. of England. Vol. VII., pp. 87-89.
Mr. Owen has made the interesting discovery that the larvæ of the wheat-moth are sometimes preyed upon by still smaller larvæ, which, having destroyed their victims, are transformed to minute black ichneumon-flies. These have not yet been obtained from any of the samples of infected wheat or corn that have come under my notice; but, from the figures given of them by Mr. Owen in “The Cultivator,” for November, 1846, they appear evidently to be Chalcidian parasites, and belong perhaps to the genus Pteromalus. Of these parasitical flies he remarks, that "some farmers had noticed large numbers among the tailings of the winnowing machine.” Where they prevail, they doubtless contribute, in no small measure, to check the increase of the moths.
The Angoumois moth is unknown in England. Hence specimens of the American insect, sent by me to my friend the late Mr. Edward Doubleday, of the British Museum, in December, 1845, were not immediately recognized by him and by Mr. Curtis, the celebrated English entomologist. Afterwards, on consulting the work of Duponchel on the Lepidoptera of France, they identified my specimens as belonging to the Butalis cerealella, the true Angoumois grain-moth, described and figured in that work. This identification is the more interesting and satisfactory, from the circumstance that I had not communicated to these gentlemen my belief that the insects were the same, and had given to them no account of the habits of my specimens, being desirous of obtaining their opinion unbiassed by my own. I am not aware that
any attempt had been made by European naturalists, before the publication of the first edition of this treatise, to determine the modern genus to which the Angoumois moth belongs, or to clear up and make known the synonymy of this species. This labor seems to have been left to an American, remote from the scene of the early and long continued depredations of the insect, and deprived of the common facilities enjoyed by European naturalists.
7. FEATHER-WINGED Moths. (Alucite.) The last tribe of Lepidopterous insects remaining to be noticed, contains the Alucitæ of Linnæus, or feather-winged moths, called PTEROPHORIDÆ by the French naturalists. These moths are easily known by their wings being divided lengthwise into narrow, fringed branches, resembling feathers. The fore wings in the genus Pterophorus are split, nearly half way, into two, and the hind wings are divided, to the shoulder-joint, into three feathers; and each of the wings, in Alucita, consists of six feathers, connected only at the joint. The antennæ of these moths are slender and tapering; the tongue is long; the feelers are two in number, and of moderate length; and the body and legs are very long and slender. When at rest their wings do not cover the body, but stand out from it on each side, not spread however, but folded together like a fan, so that only the outer part of each of the fore wings is visible. They fly slowly and feebly, some of them by day, and others only at night, and, when on the wing, they somewhat resemble the long-legged gnats. Their caterpillars are rather short and thick, are clothed with a few hairs, and have sixteen short legs. Most of them live on the leaves of low or herbaceous plants, and, when about to change to chrysalids, they fasten themselves by the hind feet and by a loop over the back, like the Lycænians. Those which belong to the genus Alucita are said to live in buds, and undergo their transformations in thin, transpar
The number of species in this tribe is small; and those that are found in this country are so few, and of so little consequence, in an economical point of view, that a particular description of them will not be necessary in this treatise.