CONCLUSIONS.

It is regrettable that no experiments were tried with the European carpet beetle, commonly, though erroneously, called "buffalo moth" (Anthrenus scrophularia), but for some unexplained reason this insect is not known as a carpet pest in Washington, and any experiments made at that point with introduced specimens would therefore be inconclusive. It is doubtful, however, that it would be found to differ greatly in resistant qualities from the rather closely allied Attagenus piceus. It should, however, be definitely experimented with, unless it has already been done by Mr. Henshaw.

The experiments just summarized seem to me to show definitely that it will be perfectly safe to keep materials infested by any of the insects mentioned above during the summer months at a temperature of from 40° to 42° F., and that the average cold-storage company, if my information as to the customary temperatures be correct, has been wasting in the neighborhood of 20° of cold.

The economic entomologist is always interested to know in cases like this what the actual saving will be in dollars and cents, but in this case it is impossible to say. It is practically impossible to estimate a definite cost for each degree of refrigeration, on account of the differences in machines, in insulation of rooms, in cost of coal at different points, and more particularly on account of the increase of cost in periods of excessive summer heat. It is plain, however, that in every such establishment every degree of temperature below that of the outside air requires a definite expenditure of coal, and, therefore, a saving of 20° of actual temperature is a saving indeed.

Mr. Fernald expressed himself as much gratified with this presentation of a new and very valuable method of controlling certain of the household pests, and stated that this subject was one in which he had been much interested for a number of years. He felt convinced of the very great importance of the temperature method of control now for the first time brought prominently to the fore.

Mr. Howard suggested that in view of the increase of the expense of this treatment the lower the temperature be maintained, if previous disinfection be given articles it would doubtless be possible to keep them with safety through the summer at a temperature of 50° F. He suggested steaming, as a preliminary disinfection, wherever practicable.

Mr. Fernald was of the opinion that such steaming of goods prior to storing is now practiced in Boston by certain storage companies. 5850-No. 6– -2

Mr. Webster presented the following paper:

THREE YEARS' STUDY OF AN OUTBREAK OF THE CHINCH BUG IN OHIO.

By F. M. WEBSTER, Wooster, Ohio.

As compared with Illinois and the States west of the Mississippi and north of the Arkansas rivers, Ohio had, until 1895, never witnessed an outbreak of chinch bug. As a consequence, almost the only farmers who had any acquaintance whatever with the pest were such as had · had experience with it in the States above mentioned, few others being able to recognize it when it appeared in their fields. There had been a slight attack in extreme southern Ohio in 1873, and a more severe one, located more centrally, in 1887 and 1888, but even in these cases the ravages were not so very severe, except locally. In traveling about over the State I have frequently observed it in limited numbers and learned of its previous occurrence in various localities in noticeable though not in destructive numbers from people who could only describe them as 66 being present at harvest time and among corn at the time of cutting and curing the fodder, and having the odor of bedbugs." It was therefore with little concern that in the summer of 1894 I noted them in limited numbers over the area indicated in fig. 1 by horizontal lines, and much more abundant where these are crossed by oblique lines. There did not appear to be any special danger, as the threatened outbreak would probably have failed to materialize had the spring of 1895 been one during which there was an average rainfall. But the season of 1895 proved a very dry one, and I fully expected trouble from somewhere, but up to June 25 no complaints were received from farmers, and I came to the conclusion that Ohio was certainly not a locality at all congenial to chinch bugs. Within two weeks, however, that opinion was entirely reversed, and hundreds of farmers appeared to discover the pest on about the same dates, and a perfect deluge of letters came pouring in, but, strangely enough, very few of them came from within the area where the pest had been observed the previous year, and consequently where they might apparently be the most confidently expected. In fig. 2 the area of attack and the relative severity are indicated as in map 1, and it will be observed that in one county only, Wyandot, was the attack as severe as during the preceding year, while over a considerable portion of the area where bugs were observed in limited numbers in 1894 we had no complaints of their appearance at all in 1895. Attention is here called to the isolated localities of occurrence that year, as these will prove of especial interest when we come to study the outbreak of the year 1896, besides indicating localities where we distributed Sporotrichum. The autumn of 1895 was very dry, and almost the entire fall brood of chinch bugs must have gone into winter quarters in a healthy condition. The spring of 1896 opened with

a moderate rainfall, except in the extreme southern portion, where' very few chinch bugs had been reported last year, so that it was, early in the season, utterly impossible to foresee what was to follow-whether we were to have a third attack or not, and in case we did, where in the whole State we were to expect the outbreak. Farmers were apprehensive of trouble and very uneasy, especially where they had felt the

1894.

effects of the ravages of the pest the year before, and to see a chinch bug on their premises was the signal for a call for aid in fighting what it was felt would, if not checked, prove even more destructive than last year. At least two farmers committed suicide on account of these troubles. We had distributed about 750 packages of Sporotrichum globuliferum last year, and notwithstanding that there seemed little hope of relief from this quarter in case the drought continued, we were

overwhelmed with applications for diseased chinch bugs. A change is certainly coming over the agricultural classes in their feeling toward applied entomology, as is witnessed by the fact that until quite recently when there was an outbreak of any destructive insect the farmer would simply watch the destruction of his crops with helpless concern, whereas now he writes to an entomologist to send him some

FIG. 2.-Map showing area in Ohio over which chinch bugs occurred in greatest abundance in 1895: area seriously affected: (from Bull. 2, n. s., Div. Ent.)

kind of disease or parasite that will destroy his enemy without further effort on his part. To supply the demand for Sporotrichum we cultivated on a mixture of beef broth and corn meal, and in this way have so far this year responded to over 1,200 requests. I mention this as indicating the fact that this year farmers were on the watch, and occurrences that in other years would have either escaped notice entirely or been ignored in case they were observed were promptly reported to us,

and will be found indicated on fig. 3 in the same manner as on the other maps. About the 10th of June we were relieved of all suspense, and it was very clear that southern Ohio would be the area ravaged this year. The reason for this is not hard to find, as up to about June 10 very little rain had fallen, and I take it that by this time the young bugs had so far developed as to be little, if at all, affected by it. This will, in some degree at least, solve the problem of the appearance of

FIG. 3.-Map showing area in Ohio over which chinch bugs occurred in 1896:

: area

the chinch bug in the south in such destructive numbers this year, while the country farther north, where the hatching takes place later, escaped with little or no destruction to farm crops, except in the extreme northeast. But the perplexing feature of the problem is in that we have them this year in greatest numbers and committing the most serious depredations, for the most part, where we heard little or nothing

1.

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