under the edge. It is useless to go into details, and we have not yet decided whether steel, whalebone, bristle or broom corn, or some other material will prove best. Prof. W. S. Barnard, of Ithaca, N. Y., is now working out the details of the gearing, and will continue to experiment with different devices and on different principles. He has already made some very important discoveries which will be duly recorded in the next report of the Commission on the subject. Another simple plan now being tried, for applying wet poison to both sides of the leaves, without involving machinery, is by a long, heavy fringe upon which the poison-fluid drips, and from which it is wiped off by the leaves as they are pulled through its pendent parts, which hang down among the branches while it is carried over the row. Another principle will be practically applied and worked out, if possible, by Mr. J. D. Cross, of Alabama. It is to throw the powder behind a cultivator by means of a revolving fan, worked by a spring to be wound up at intervals, so that the plant may be poisoned without extra labor when it is being for the last time cultivated or laid by. It is unnecessary to allude here to experiments that have given no practical results.

on.

EARLY POISONING.

The importance of poisoning early, or when the very first appearance of the worm is manifest, cannot be too strongly insisted Wherever it has been done early and judiciously the crop has been saved, and the contrast between the poisoned fields and those not poisoned is most marked. The latter have been defoliated over a month, and will yield, on an average, but one-third as much cotton as the former, and that of an inferior quality.

WEATHER: CONCLUSION.

The weather throughout most of the cotton belt has been unfavorably wet, and, indeed, the persistent rains have greatly interfered with the experiments and the work of the Commission. Yet we have reached a stage in the management of the worm when there is no longer any excuse for loss by its ravages, and with the results of this year's labors of the Commission, I feel that I have measurably accomplished what I set out to do three years ago, viz. : to get thorough and accurate knowledge of the habits of the principal insects injuriously affecting the cotton plant - a knowledge

which did not then exist - and to learn best how to control them. The Caterpillar and the Boll-worm, the two worst of these enemies, will soon cease to be a cause of anxiety to intelligent and enterprising planters. How best to overcome in this connection the negligence and indisposition of the more careless and ignorant of the cultivators, of whom there are so many among the freedmen, is a question which I may consider at some future time.

THE HITHERTO UNKNOWN LIFE-HABITS OF TWO GENERA OF BEEFLIES (Bombyliidae) By C. V. RILEY, of Washington, D. C.

[ABSTRACT.]

THE paper gives the life-history of Systochus oreas O. S. and of Triodites mus O. S. and shows that their larvæ have the same habit of preying on locust eggs. It calls attention to the parallelism in the life-history of the Bee-flies and of the Blister-beetles. The Bombyliidae (accepting the more recent expansion of the family), so far as their habits have been hitherto recorded, were known to prey parasitically in the larva state upon the larva either of burrowing bees (genera Anthophora, Andrena, Halictus, Colletes, etc.), of mud-daubing wasps (Trypoxylon, etc.), or on the pupæ of certain Lepidoptera (e. g., Limacodes). Yet certain genera develop in the egg-masses of the Acrididæ, feeding upon the eggs. So the habit of the Meloïdæ, so far as known up to the year 1877, was to live parasitically in the cells of either burrowing bees or mason bees, though certain genera, e. g.: Epicauta and Macrobasis, were then shown to prey on locust eggs. (See Proc. of the Association for 1878, B., p. 18.) The abundance of both the Bombyliida and Meloïda in the western country is referred to as directly connected with the prevalence of locusts there, and the facts of retarded development in the early stages of both families are recorded and explained as a characteristic beneficial to the species which must depend on such uncertain food as the eggs of insects like the migratory locusts, which in some years prevail in great abundance and in others become scarce or are not found at all, in given localities.

ON LIGHTNING BUGS. BY JOHN L. LECONTE, of Philadelphia, Pa.

SINCE the publication of my synopsis of Lampyridæ in 1851 (Proc. Acad. Nat. Sc., Phila, 1851, 331), but few species of the family have been described in this country, and no very important improvement has been made in their classification; about the same time I published in the Journal of the same Society (New Ser., i, 73) a synopsis of Lycidæ, one of the sub-families of Lampyridæ. This last mentioned synopsis is one of my early and crude contributions to science, which, if the study of Natural History had been farther advanced in this country, would have been kindly suppressed, or returned to me for revision. In the Classification of the Coleoptera of N. A., I have established the family with different limits than those adopted by European writers at that time (1861), and constituted it of the three following sub-families, which are here more fully defined:

LYCIDE.

Middle coxæ distant, epipleure wanting. . Middle coxæ contiguous, epipleuræ usually wide at base, episterna of metathorax with inner margin sinuate . . . LAMPYRIDÆ. Middle coxæ contiguous, epipleuræ narrow at base, episterna of metathorax not sinuate on inner margin .. .. TELEPHORIDE.

A detail of the minor groups and tribes composing these families would be here out of place, and may be found in my Classification; they will be fully exposed in a synopsis of the genera and species now ready for press. Otherwise, the habits and life history of a few species have been more or less thoroughly observed and recorded.

For the past few years I have been trying to procure material to enable me to make a more complete synopsis of the genera and species, and a better exposition of their relations to each other than I had been able previously to give.1

For furnishing series of larvæ, pupæ and imagines of species from her vicinity, I am under especial obligations to Mrs. V. O. King, of Austin, Texas. An excellent account of the transformations of Pleotomus pallens from her pen has been printed in Psyche, iii, 51 (1880), and equally valuable life-histories of other species may be expected in the future.

1I would here mention that no reference is made in the text to the important general work of Lacordaire, or the excellent faunal European work of Du Val, in which the genera have been tabulated in a convenient manner, but without special reference to our species, except what has been derived from my own works cited above.

I congratulate myself, that by the slow progress of my studies and the tardy manner in which some of my correspondents have replied to my request for larger series of specimens, I am now able to profit by the recent publications of Mr. C. O. Waterhouse 2 on Lycidæ, and Rev. H. S. Gorham3 on Lampyridæ.

The object of the present essay is simply to give some popular information in regard to the characters of these insects, and to correlate, so far as our species may permit, the light-giving faculty with other structures; I will, therefore, not enter here into a close analysis of the relations of the genera.

It is then sufficient to say, that none of the Lycidæ or Telephoridæ possess any light-giving organs, and that they are diurnal in their habits. In some of the Lycidæ the front part of the head is prolonged into a beak, and in many of them the elytra are very large, expanded and coarsely reticulated. The peculiar structures of some Telephorida will be noticed farther on.

The Lampyridæ proper comprise all the luminous species, though this faculty is possessed by them in a very unequal degree, and in some genera and species of diurnal habits is quite wanting. For our present purposes their division may be indicated into tribes and groups as follows:

A. Side pieces of Metathorax narrow;

a. and similar or nearly so; antennæ long, last joint simple.

b. and conspicuously different; antennæ short, last joint with acicular appendage.

B. Side pieces of metathorax wide (unknown); palpi very unequal, mouth organs more developed.

The series A a contains the largest number of genera and species, and exhibits a gradation from Matheteus, with widely separated pectinate antennæ, and general Lyciform appearance, through Photinus, with approximate filiform antennæ, and head retracted under the prothorax, to Photuris, with the antennæ filiform, and the head partly exposed. There is thus a continuous line of affinities in this series from the diurnal Lycidæ to the diurnal Telephorida.

Now besides the gradations in structure just mentioned there are great differences in the sizes of the eyes, and in the develop

2 Br. Mus. Cat. Illustrations; Coleoptera, Part 1, Lycidæ, 1879.

3 Trans. Ent. Soc. London, 1880, p. 1, 63, 83, and Proc. loc. cit. infra.

ment of the light organs. In the species usually seen flying by day (Lucidota, Ellychnia, etc.) the light organs are indicated by feeble yellowish spots on the last ventral segments, but do not seem to possess any light-giving power; in these the eyes are lateral, rather small in, but larger and more convex in ; they are widely separated above and beneath as in Lycida.

The series Ab contains a much smaller number of genera, and in them the antennæ are approximate, usually filiform, rarely (Pleotomus) bipectinate. The number of joints varies from 9 to 14, and the last joint has at the end a small acicular appendage simulating an additional joint. The eyes of the are excessively large, almost contiguous above and beneath, leaving very little. room for the mouth and antennæ; in the 9 the eyes are moderate, or even small, lateral and widely separated. The light organs are varied, sometimes brilliant in both sexes, sometimes weak in both sexes, and sometimes brilliant only in the . Their food consists of small terrestrial mollusca.

The third category, B, consists of Phengodes and allied genera in which the side pieces of the metathorax are wide. I know nothing by observation of the luminous qualities of these insects, of which only males are known. They are all rare, and I have seen none alive. But we here owe our special thanks to Mrs. King for the patient quest which has been rewarded by the discovery of the pupa of Phengodes, and which will probably result in another season in the detection of the larva.4

I am also indebted to Mrs. King for a larva of Mastinocerus, of slender, cylindrical form and pale color. It was feebly luminous, and lived upon small snails. The perfect insect is thus mentioned in a letter, the observations being made upon a specimen attracted by the lamp: "June 4th saw running rapidly over the table near a lighted lamp, a small Coleopter; it was twisting its abdomen up over its wings, and evidently trying to straighten them out, as they seemed moist and twisted at their ends. The general appearance suggested Mastinocerus, and acting on this thought, I captured it and sat up till a late hour to be assured of the truth. The

4 It is still uncertain whether the large luminous larvæ described by Baron Osten Sacken (Proc. Ent. Soc. Phila., i, 125, pl. 1, f. 8) belong to the Elateride Melanactes or to Phengodes. Species of both genera are found in nearly all parts of the United States, but though the larvæ seem to resemble that of Mastinocerus referred to in the text more than any described Elateride larvæ, it is more probable that they should be referred to the latter family.