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slightest touch or may fall off of its own weight. After drying there are no soft parts left, but only a hollow skeleton throughout. The body fluids before death are, sometimes at least, literally crowded with germs. In one case, for example, the hind femur of a sick hopper that was still able to move about was cut across and the moist muscle wiped on a cover-glass, which showed the bacilli as abundant as the red corpuscles in a person's blood. Numerous cultures in agar were made from this and other hoppers in different stages of the disease, but in all cases cultures were obtained exactly resembling those of Bacterium termo, and we could isolate no other organism that would kill the hop. pers when fed back to them. This close resemblance of these germs to termo led me to carry on a series of parallel experiments with these cultures and pure cultures of termo froin beef broth. It was found that either germ sprayed on alfalfa and fed to healthy hoppers would kill inside of forty-eight hours, and if directly inoculated by needle thrusts into the bodies of the grasshoppers either would kill inside of twenty-four hours, while none would die in check cages where the insects received similar thrusts with sterilized needles. These results with termo alone were of much interest to me, as they suggest a possible new use of this, the most beneficial of all the Schizomycetes.

Insects reared from the dead grasshoppers.-It was common to find small maggots in the putrid bodies of hoppers that had been some time dead, but no such thing was found in the bodies of the sick hoppers that were still alive. I give below a list of the Diptera and Hymenoptera bred from the dead boppers. The Diptera were determined by Mr. Coquillett, and the Hymenoptera by Mr. Ashimead. Mr. Coquillett also wrote, in reply to a question from me, that he did not think the Diptera could have been parasitic, but that they probably fed upon the dead bodies of the grasshoppers. The Diptera were

Sarcophaga cinbicis Town.,
Sarcophaga sarracenia Riley,
Sarcophaga, sp.
Cyrtoneura stabulans Fall.,

Helicobia lieiicis Town.
The Hymenoptera were-

Aphareta musca Ash.,
Perilampus sp.

CONCLUDING REMARKS.

From my work and observations with the grasshopper disease I feel warranted in drawing the following conclusions:

1. That the grasshoppers have died in large numbers of some bacterial disease in Colorado during the summers of 1895 and 1896.

2. That the disease is most prevalent in a wet time and upon low ground.

3. That the disease may be spread artificially when the weather conditions are favorable, but that it is impossible to spread the disease with any degree of success in a dry time, and especially upon high ground.

4. That the disease confines its attacks almost exclusively to two species, Melanoplus bivittatus and M. femur-rubrum, so far as I have been able to observe, and that it attacks these equally in all stages of development.

5. As I have seen occasional dead grasshoppers clinging to the tops of plants in nearly every part of the State that I have visited, some of these places at long distances from points of artificial introduction of the disease, I believe it is probable that the disease is present in small amount in most localities and that an artificial introduction will usually do little or no good, though I should strongly advise the artificial introduction of the disease in fields not having it, whenever possible.

6. That the unusual appearance of the disease last year was due chiefly to the very extraordinary rainfall and the large number of rainy days during June and July.

A SIMPLE DEVICE FOR THE PREPARATION OF OIL EMULSIONS.

By II. A. MORGAN, Baton Rouge, La.

The fact that the ingredients which enter into a kerosene emulsion are usually on band, or may be easily procured at very little cost, together with the general efficiency of a well-prepared emulsion as an insecticide, recommends it at once to everyone, but the difficulty of getting a thorough emulsion and the danger of using one improperly prepared have had a tendency to offset the good qualities of which we have just spoken and to cause oil emulsions to become unpopular. This I have found to be the case with people who have only a few trees or plants affected with insects and who are not prepared with force pumps to be used to churn the emulsion.

It is to accommodate those who have found it difficult to churn the ingredients to a milk-like condition, and, too, to save the valves of the force pumps, which I have found become materially impaired by foreing the hot material through them, that I recommend the use of a simple churn, which may be described as follows:

The main portion consists of a tin cylinder 20 to 24 inches long and 4 inches in diameter; however, the diameter may be such that the churn will conveniently fit into the opening of a knapsack sprayer, for it may be often convenient to churn the ingredients within the sprayer. Within an inch of the bottom of the cylinder is a row of seven small openings (of course the number may vary, but in a 4-inch cylinder seven, each with a diameter not more than three eighths of an inch, will be found sufficient). In the bottom of the cylinder there is in the figure

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a large opening three-fourths of an inch in diameter, which I had put

there for drainage after removing the churn, but I believe the churn operates better without the opening.

The plunger consists of a tin cone attached to a three-eighths-inch iron rod, at the other end of which is attached a handle, which may project any distance above the top of the cyl

inder. The cone has a base of such diameter e

as will nicely fit into the cylinder, and may be from 3 to 34 inches high. About three-fourths of an inch above the base is a row of five openings of the same size as those in the base of the cylinders; here, too, the number of open. ings may vary, but I have found five ample. In the center of the base of the cone is a large opening three-fourths of an inch in diameter.

The churn may be used with or without a lid. I find it saves time, but wastes a little material at times, to do without the cover.

The entire cost of making this churn should Fig. 5.- Device for preparing

not be more than 40 or 50 cents.

The figure which accompanies this paper may assist in understanding the general make-up of the pump.

oil emulsions.

Mr. Bethune presented the following resolution relative to the late Dr. C. V. Riley, which was unanimously adopted:

This association at its first meeting since the death of Dr. C. V. Riley, last September, who was its originator and first president, desires to place upon record its deep regret at the loss which it has sustained by his untimely removal. He was acknowledged to be the highest authority in this or any other country on economic entomology, and to have held a rarely equaled reputation for scientific work. While entomological science has been deprived of one of its ablest exponents, the members of this association feel also that they have personally to lament the loss of a true and warm-hearted friend.

The committee appointed to nominate officers for the ensuing year, consisting of Messrs. Smith, Lintner, and Forbush, made the following nominations:

President, F. M. Webster, Wooster, Ohio.
First vice-president, Herbert Osborn, Ames, Iowa.
Second vice-president, Lawrence Bruer, Lincoln, Nebr.
Secretary, C. L. Marlatt, Washington, D. (.
A ballot resulted in the unanimous election of the persons nominated.

On motion of Mr. Lintner', the time and place of meeting was fixed as heretofore, viz, on the two days preceding the general sessions of the American Association for the Advancement of Science, and at the place selected for the meeting of that association.*

On motion of Mr. Howard, the reading and adoption of the rough minutes of the entire session were dispensed with.

On motion of Mr. Hopkins, the United States Department of Agriculture was requested to publish the proceedings of the session just closing, as heretofore.

Mr. Lintner presented the following resolution, which was unani. mously adopted :

Whereas it has come to the knowledge of the members of this association that a general index to the seven volumes of Insect Life has been prepared and is in readiness for publication, and that question of its publ ation has arisen in consideration of the expense that would attend it: Therefore,

Be it resolved, That this association most earnestly requests the speedy publication of the index as an almost indispensable supplement to a series of volumes of incalculable value to every economic entomologist.

On motion of Mr. Howard, a vote of thanks was given to the local committee for their efforts in making arrangements for the present session of the association.

On motion of Mr. Howard, a vote of thanks was given to Mr. E. P. Van Duzee for his efforts in making preliminary arrangements for hotel accommodations for the entomologists.

On motion of Mr. Hopkins, a vote of thanks was given to the president and secretary for the eminently satisfactory manner in which they had conducted the business of the session.

The association then adjourned, subject to the call of the executive committee.

C. L. MARLATT, Secretary.

Detroit, Mich., August 6, 1897.

CONSTITUTION AND BY-LAWS OF THE ASSOCIATION OF

ECONOMIC ENTOMOLOGISTS. [Adopted at a meeting held at Toronto, Canada, August 29–30, 1889, and subsequently amended.]

CONSTITUTION.

SECTION I. This association shall be known as the Association of Official Economic Entomologists.

Section II. Its objects shall be: (1) To discuss new diecoveries, to exchange experiences, and to carefully consider the best methods of work; (2) to give opportunity to individual workers of announcing proposed investigations, so as to bring out suggestions and prevent unnecessary duplication of work; (3) to suggest when possible certain lines of investigation upon subjects of general interest; () to promote the study and advance the science of entomology.

SECTION III. The membership shall be contined to workers in economic entomology. All economic entomologists employed by the General or State governments or by the State experimental stations or by any agricultural or borticultural associattion, and all teachers of economic entomology in educational institutions may become members of the association by transmitting proper credentials to the secretary and by authorizing him to sign their names to this constitution. Other persons engaged in practical work in economic entomology may be elected by a two-tbirds vote of the members present at a regular meeting and shall be termed associate members. Members residing outside of the l'nited States or Canada shall be designated foreign members. Associate and foreign members shall not be entitled to holil office or to vote.

SECTION IV. The officers shall consist of a president, two vice-presidents, and a secretary, to be elected annually, who shall perform the duties customarily incumbent upon their respective offices. The president shall not hold oftice for two consecutive terms.

SECTION V. The annual meeting shall be held at such place and time as may be decided upon by the association at the previons annual meeting. Special meetings may be called by a majority of the officers, or shall be called on the written request of not less than five members. Eight members shall constitute a quorum for the transaction of business.

SECTION VI. The mode of publication of the proceedings of the association shall be decided upon by open vote at each annual meeting.

SECTION VII. Ali proposed alterations or amendments to this constitution shall be referred to a select committee of three at any regular meeting, and after a report from such committee may be adopted by a two-thirds vote of the members present; Prorided, That a written notice of the proposed amendment has been sent to every voting member of the association at least one month prior to date of action.

BY-LAWS.

Adopted at a meeting held at Washington, DC., November 12, 1889.)

ARTICLE I.-Of members, SECTION 1. The classes of members are defined in the constitution, as are their rights to vote or hold office. Members of all kinds have equal privileges as to pres. entation of papers and in the scientific discussions at the regular meetings, and may, by permission of the presiding otticer, speak on business questions before the association.

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