Mr. Kirkland described these experiments, which were quite varied and included the poisoning of portions of leaves or of one or both surfaces, and also tests with larvæ of different ages. The result of the whole series would seem to indicate that the presence of the poison was not noticed by larvæ and had little if any effect in deterring them from feeding.

Considerable discussion followed, various members supporting both sides of the question.

Mr. Smith stated that his experience was confirmatory of Mr. Marlatt's, and he had noticed the same repugnance in the case of the elm leaf-beetle. He was quite inclined to agree with Mr. Marlatt that this repugnance, due to the presence of poison, is the explanation of the slow action of arsenicals, which is of rather common experience.

Mr. Fernald explained that the experiments under his direction had been with the larvæ of the gypsy moth, which in this and other ways manifest characteristics and powers of resistance widely different from other larvæ.

Mr. Johnson described an experience which he had had with the apple leaf-skeletonizer, attended with similar manifestation of repug. nance of the larva to poisoned leaves. He described feeding experi ments in cages in which 100 larvæ were included in each cage and fed with leaves poisoned at a definite strength. In one instance the larvæ refused to feed for three days.

Mr. Webster, referring to the statement concerning the use of oily washes on trees by Mr. Marlatt, described an experience with the use of pure kerosene on peach trees for the San Jose scale in Ohio. The trees had been cut back rather severely and were in December sprayed thoroughly on trunk and branches with pure kerosene. Upon examination in March these trees were in thrifty condition and presented no injury from the application. He was so pleased with the results that he purposes to recommend the use of pure oil, and stated that many orchards would probably be sprayed with this substance the ensuing winter. He further called attention to the fact that the Bordeaux mixture sprayed on plants often afforded protection by rendering the foliage distasteful in much the same manner as an arsenical. He instanced particularly the benefits of Bordeaux as a means of protecting potato vines from the attacks of Diabrotica vittata. He referred also to the fact that no general deductions can be made from the habits or behavior of any particular insects with poisons, and that with different species vastly different results are to be expected. He referred to his experience with the grapevine Fidia, which he had kept in a breeding cage through which a living grapevine was passed which had been poisoned with arsenicals at the rate of 4 ounces to 50 gallons. The beetles lived for several days on this poisoned food. He referred also to the fact that the different results obtained with the same insect are not always due to faulty material, but rather to the men who make the

applications, since farmers are highly unreliable and can very rarely be depended upon to make applications properly.

Mr. Fletcher agreed with Mr. Webster as to the variability manifested by different insects under treatment with insecticides, instancing as a striking case in point the gypsy moth. He spoke of the great value of the work of the gypsy moth committee, particularly as brought together in the recently published report, which contains much that is of interest on this and other subjects. Referring to the value of Bordeaux mixture as a means of protection, he said that he had found it quite effective against Crepidodera (?) when Paris green failed entirely. He also referred to the use of lime with Paris green and the value of this combination as a safeguard against scalding.

Mr. Kirkland, referring again to the experience of the gypsy moth committee, stated that results seemed to indicate no value whatever from the combination of lime with Paris green. The lime, if it had any action, would simply break down the Paris green.

Mr. Howard suggested that the action of lime in determining the effect of the arsenical on foliage and larvæ would depend largely on the amount of lime employed.

Mr. Fletcher agreed with the probability of the amount of lime used being important and asked for information as to the exact proportions that had been found to be most desirable.

Mr. Smith stated that the amount of lime necessary to be employed to neutralize Paris green had been experimentally determined by the chemist of the New Brunswick Station, and that he had published the data in a report of the station. He was convinced that the benefit of the addition of lime to arsenicals had been demonstrated beyond question, and he had always so recommended it.

Mr. Fernald stated that he formerly agreed with Mr. Smith as to the desirability of the use of lime and had recommended its use up to the time of these experiments. He asked Mr. Forbush for his experience with the use of this arsenical with or without lime.

Mr. Forbush stated that his experience was that it made very little difference whether lime was added or not. In some instances results were less satisfactory with lime than where it had not been added. In some instances, also, foliage was burned most where lime had been used. He stated that he had early discontinued the use of lime with arsenicals in work against the gypsy moth.

Mr. Smith stated that he had constantly recommended the use of lime in correspondence and publications and felt that its addition to arsenicals was of decided value.

Referring to the subject of insecticide soaps, Mr. Smith stated that he had found the same difficulties mentioned in Mr. Marlatt's paper on the subject, and in some instances where the soaps had been used no beneficial results had followed whatever, to the very considerable discouragement of farmers who had gone to much expense to procure

materials and make the applications. He was convinced that to get good results it will be necessary for each farmer to make the soap for himself. He had found also that Leggett's soap was excellent in quality and thoroughly satisfactory, killing the scales completely, but that it was much too expensive for practical use on a large scale. He said that some farmers have already had very good results with soaps made by themselves. He was of the opinion that as a rule farmers will be quite willing to undertake the manufacture of soap, especially as they would be in the majority of cases more willing to assume the trouble of manufacture rather than go to the expense of purchasing soap from some dealer. In California a soap containing a definite composition is demanded, and a method of determining the amount of moisture, viz, by drying, is practiced.

Referring to the recommendation of Mr. Marlatt of the arsenite of lead in preference to the arsenate, Mr. Smith further stated that the easy preparation of the latter is an argument in favor of its use by farmers, the preparation of the arsenite being more difficult and attended with some risk of poisoning if undertaken by persons unfamiliar with the precautions necessary. Referring to Mr. Webster's report of the use of kerosene pure on the trees, he was of the opinion that such application would kill the trees outright.

In answer to a question from Mr. Howard, Mr. Smith stated that wetting the bark of trees with kerosene and firing it to kill scale insects had in his experience been satisfactory and had not worked injury to the plants. The treatment can only be made on an absolutely calm day. With even a little breeze blowing the kerosene will not burn on the windy side. On smooth-barked trees where the bark is green and healthy the kerosene will not burn at all, and it is only on trees that have a certain amount of dead surface bark or have it covered with lichens, mosses, or the like that one can get any satisfactory burning. Practically the measure is useless except on old trees.

Mr. Kirkland, referring to the common method of preparing arsenate of lead, stated that if the crude acetate of lead be used, which is considerably cheaper than the refined article, it will be necessary to dis solve it in warm water, as it will not dissolve readily in cold water. He also referred to the danger of arsenical poisoning attending the manufacture of arsenite of lead by farmers and others who are not used to handling the substance and are not supplied with proper apparatus.

Mr. Lintner, referring to Mr. Howard's paper on the elm leaf-beetle, stated that he still held to his former conclusions that the larva of the elm leaf-beetle do not drop to the ground in any numbers. He was not by any means convinced that the case referred to by Mr. Howard of the presence of pupa on horse-chestnut was at all conclusive. He said that the larvæ have a very great climbing tendency, instancing a number of cases corroborating this fact. He had taken in one instance no less than 21 larvæ from a deserted cocoon of Orgyia on the trunk of a tree. He said that there was an undoubted second brood of the elm

leaf beetle at Albany the present season, and described the circumstances attending its appearance. In this instance the second brood of larvæ appeared on the trees which had not been attacked by the first brood.

Mr. Smith said that he had found, the present season, no trace of a second brood at New Brunswick, N. J., although everything was favorable for the appearance of a second brood, in view of the presence of many trees in good foliage. The trees on the grounds of the college campus were this year in exceptionally superior condition. He referred also to the discovery of larvæ and pupa under the bark of other trees than elm, and supported Mr. Howard in his conclusions. There was abundant opportunity for the appearance of a second brood, but, in point of fact, the beetles had already practically disappeared into their hibernating retreats.

Mr. Howard, in answer to Mr. Lintner's criticism, stated that he saw larvæ descending the horse-chestnut from a point above the main crotch, and further stated that the intervening ground space between the elms and the horse chestnut was covered with close, short grass, so that it was out of the question for the larvae to have reached it in any way except by falling on it from the overhanging elm branches. No other explanation was possible. He referred also to the case reported by Mr. J. W. Clark at the last meeting, where the branches of an elm extended over a house, which had also no other possible explanation than that the larvæ fell directly from the branches to the ground.

Mr. Johnson stated that at the Maryland Experiment Station, by order of the chemist, Mr. Patterson, bands of dendrolene had been put about the trunks of elms in the station yard to keep the larvæ from ascending. Mr. Patterson stated that he had observed larvæ ascending the trees, but, after the application of this lime, they accumulated about it or would fall back to the ground and could then be easily destroyed.

Mr. Howard stated that the second brood of the elm leaf beetle was very small this year in Washington. His explanation of this fact was that the first brood had not been large and there had been comparatively little damage to foliage, so that when the second brood arrived there was no second crop of new tender leaves to induce them to oviposit, the results in this respect being entirely different from last year, when the first generation was large and entirely defoliated many trees, and the consequent throwing out of a second crop of leaves induced the beetles to oviposit it for a second generation. With regard to the distribution of this insect, Mr. Howard said that he had found it abundant at Troy, and the farthest northern limit so far discovered for them was Mechanicsville in the Hudson River valley.

Mr. Fernald said that they were not increasing at Amherst, and were no more abundant this year than last at that point.

MORNING SESSION, AUGUST 22, 1896.

The following new members were proposed and duly elected:

M. F. Adams, Buffalo, N. Y. Proposed by Mr. Slingerland.

Lewis Collins, Brooklyn, N. Y. Proposed by Mr. Howard.

W. E. Rumsey, Morgantown, W. Va. Proposed by Mr. Hopkins.

On motion of Mr. Smith, the chair appointed a committee consisting of Messrs. Smith, Lintner, and Forbush to nominate officers for the ensuing year.

The following paper was read by Mr. Smith:

SCALE INSECTS AND THEIR ENEMIES IN CALIFORNIA.

By JOHN B. SMITH, New Brunswick, N. J.

[Author's abstract.']

So much has been published on the subject of the beneficial effects of predaceous insects introduced into California to destroy injurious scales that, the farmers of New Jersey felt as if a similar method should be at least tried in New Jersey to rid them, if possible, of the San Jose or pernicious scale.

The matter was discussed in the Horticultural Society and in the New Jersey State board of agriculture with the result that an appropriation was made by the legislature of the State for the purpose of investigating the scale in California and for introducing into New Jersey such of its enemies as might offer a fair chance of being beneficial and of maintaining themselves in its climate. The investigation was made in May and June, principally in the southern parts of California, and covering the fruit growing regions as far north as Marysville, in the Sacramento Valley. Specifically, the points touched were Los Angeles, Santa Barbara, Elwood, San Diego, National City, Riverside, San Bernardino, Ontario, Pomona, Clermont, Pasadena, San Francisco, Berkeley, San Jose, Mountain View, Palo Alto, Sacramento, and Marysville.

Throughout the State, or rather wherever examination was made, the San Jose scale was still found to be present in more or less considerable numbers; but south of San Francisco it was nowhere found in troublesome quantities. North of that point, except in the immediate vicinity of San Francisco, the scale was still a dangerous and troublesome insect and was kept in check only by persistent work on the part of the growers, the favorite remedy being the lime, sulphur, and salt wash. This seems to be entirely satisfactory as used in California, and in the Marysville region, that is, in Yuba and Sutter counties, every grower sprays his orchard, no matter how large. Thousands of fruit trees are sometimes massed together, and tons upon tons of the

The fall account of this subject will be found in the Annual Report of the New Jersey State Experiment Station for 1896,