« AnteriorContinuar »
nursery stock that is infested with the San Jose scale, or of distributing and establishing colonies of any injurious insect, except the gypsy moth. Nor is there, so far as I know, any law in the land to prevent the importation of injurious insects from any other country,
I have generally felt very shy of legal enactments, because they are so often couched in language quite beyond my comprehension, and in many cases they seem to require a "Philadelphia lawyer" to interpret them, and even then two lawyers frequently differ in their interpretation of the same legal point. I am therefore of the opinion that there is need of great clearness and simplicity in the wording of an act, and also that it would be wise to have more or less uniform laws in all the States concerning those injurious insects which are, or are liable to be, generally distributed through the country. In this matter we should also consider our nearest neighbors, Canada and Mexico, for, while politically distinct from us, entomologically there is no dividing line.
In conclusion allow me to congratulate you on the growth, importance, and success of this association, and bid each and every member God. speed and help in his chosen field of labor, assuring him that every good piece of work he may perform will not only redound to his credit, but will add to the sum total of human knowledge and human happiness.
Following the reading of the president's address, the reports of officers and committees were listened to.
The secretary presented a report in which the list of active members of the association was shown to be 78 and the foreign members 22. The same officer also presented a statement of the receipts and disbursements of funds of the association for the year.
An auditing committee of two, consisting of Mr. Smith and Mr. Hopkins, was appointed to examine the accounts, and, on motion of Mr. Smith, it was ordered to enforce the collection of the annual assessment provided for in the by-laws of 50 cents per member.
The following new foreign members were proposed and duly elected: Mr. Charles P. Lounsbury, Department of Agriculture, Cape Town, Cape of Good Hope, South Africa. Proposed by Mr. Smith.
Mr. Fred. Enock, 21 Manor Gardens, Holloway, London, England. Proposed by Mr. Howard.
Dr. Enzio Reuter, Fredriksgatan 45, Helsingfors, Finland, Russia. Proposed by Mr. Howard.
Mr. Frederick B. Theobald, lecturer in entomology and zoology, Agricultural College, Wyecourt, Kent County, England. Proposed by Mr. Webster.
Dr. Antonio Berlese, R. Scuola superiore de agricoltura, Portici, Italy. Proposed by Mr. Webster.
Dr. Paul Marchal, chef des travaux à la Station entomologique de Paris, 16 rue Claude Bernard, Paris, France. Proposed by Mr. Webster.
Mr. W. C. Grasby, Parkside, Adelaide, South Australia. Proposed by Mr. Webster. The following new active members were proposed and elected: Mr. W. G. Johnson, Agricultural College, College Station, Md. Proposed by Mr. Marlatt.
Mr. E. E. Bogue, Agricultural Experiment Station, Stillwater, Okla. Proposed by Mr. Howard.
Mr. James S. Hine, Wooster, Ohio. Proposed by Mr. Webster.
On motion of Mr. Howard, it was ordered that a joint meeting be arranged between the Association of Economic Entomologists and the Society for the Promotion of Agricultural Science for the reading or presentation of papers which would be of interest to both societies. Messrs. Howard and Bethune were appointed a committee to arrange such joint meeting.
On motion of Mr. Smith, the president and secretary were constituted a committee on programme.
Mr. Howard then read the first paper, entitled :
SOME TEMPERATURE EFFECTS ON HOUSEHOLD INSECTS.
By L. 0. HOWARD, Washington, D, C. There has been a rapid increase in the number of cold-storage plants in large cities during the last few years, and there has been a corresponding development in the uses to which they have been put. A department which has grown to quite extensive proportions is the cold storage of furs, rugs, and valuable woolen goods generally during the summer months to prevent the work of the larvæ of clothes moths and clothes beetles and allied insects.
That a certain degree of cold would result in inactivity on the part of these insects was a foregone conclusion, and as a result of the general understanding to this effect the first advertisements of cold-storage firms for furs and rugs met with an immediate response from the wealthier inhabitants of our larger cities. The first trials proving satisfactory, the custom continued and grew until at present it is recognized as by far the safest method of keeping such property during the heated months, and until it has become one of the principal sources of revenue of many cold-storage companies and practically the sole source of revenue of many others. So satisfactory has it proved that the writer, in addressing the Washington Club (an organization composed entirely of wealthy or well-to-do women) last winter, did not consider it worth while to mention any other remedy against clothes moths. Had he, however, been addressing an audience of housekeepers to whom a small sum of money would be an object, other remedies would have been mentioned.
As a matter of course the expense of this process to the owners of furs and woolen goods is necessitated by the expense of operating the coldstorage plant, and anything which will reduce the cost will enable a reduction of the charges for storage, and this brings us directly to the object of this paper,
Early in the present year the Quincy Market Cold-Storage Company of Boston, at the advice of Mr. John G. Jack, of the Arnold Arboretum, applied to the writer for information as to the exact or approximate temperature at which goods of this class should be kept in order to maintain in a state of inactivity any destructive insects which the goods might contain. It was stated that the company was in the habit of carrying eggs and fruit at temperatures ranging from 32° to 40° F. and butter and poultry at from 12° to 20°, and that recent applications for storage room for furs, felt, and different kinds of woolen goods found the company at a loss to know the necessary degree of cold. The practical importance of the inquiry appeared at once from the fact that every extra degree of cold means a more or less definite expense to the company, and they were, therefore, anxious to keep the goods at as high a temperature as would be consistent with perfect safety from insects.
Much to his regret the writer was unable to give the Boston company the definite information which it desired. He searched entomological literature for facts bearing on the subject and consulted his experienced assistants in the Division of Entomology of the United States Department of Agriculture without satisfaction, and was finally obliged to make the indefinite and unsatisfactory reply that in his opinion a temperature ot' not more than 400 F. would in all probability keep any of the insects concerned in an inactive condition. He advised careful experiment, and has since learned that this company has utilized the services of Mr. Samuel Henshaw, of Boston, in this experimental work, although the results are not yet known.
Soon after this correspondence and futile investigation of the literature a similar query was received from a Western cold-storage firm, and correspondence with this firm and subsequent investigation of the methods in use by other firms showed that many companies engaged in this business have not considered it worth while to inform themselves on this important point, but have, in their desire to make a sure thing of it," kept this class of goods systematically at a most unnecessarily low temperature, and have thus practically thrown away large sums of
As an example of the facts ascertained and as a preliminary to what follows it may be stated that a prominent Southern firm first places furs and woolens in what is called the “freezing room” at a temperature of 18° F. for a week or more and afterwards stores them permanently at a uniform temperature of 240 F.
The writer then decided that the importance of the subject well warranted experiment, and he decided to apply to some local company for facilities. At this juncture he was greatly pleased to receive a call from Dr. Albert M, Read, manager of the storage warehouse
department of the American Security and Trust Company, of Washing. ton, who had come to consult him about certain insects found in stored woolens, and who, he found, had already begun a series of experiments in just this direction. Dr. Read very obligingly placed at his disposal a well-equipped cold-storage experimental closet which he had had constructed for his own work, and further made careful observations himself, with daily notes upon different species which were furnished to him. In addition, he has since placed at the writer's disposal the notes which he has made upon material collected by himself from goods sent in for storage.
The series of experiments is by no means yet completed, but the results already reached seem to the writer to be of such value as to deserve immediate publicity. It will not be necessary to present the notes in full, but simply the facts so far learned about each species experimented with. The writer wishes it distinctly understood that the notes upon which the statements are based have been made solely by Dr. Read, who has entered upon the investigation with an interest not entirely based upon its economic aspects.
THE COMMON CLOTHES MOTH (Tinea biselliella).—Eggs.—Recently laid eggs of this species were sent Dr. Read May 2 and were immedi. ately placed at a temperature of 37° F. June 16 (the temperature in
° the interim having varied from 340 to 400) they were taken out for examination and kept for twenty-four hours at a temperature of 780. No change could be seen, and they were placed back in cold room, where they have since remained without hatching, at an average temperature of about 340,
Adult.— Experiments upon adults are necessarily more or less unsatisfactory, but here is one of interest. One small bundle of rugs (4 feet long and 1 foot in diameter) out of a large consignment which was found to be swarming with moths was saved from the general cleaning and heating, was rolled lightly in burlap, and placed in test room at a temperature of 620 F. June 21, at 4 p. m., the brine was turned on. June 22, 10 a. m., temperature 320, nearly all of the moths were dead, those alive being at middle of bundle. June 24, temperature 409, very few were still alive, and those were inactive. June 25, temperature 31°, all were dead.
Larva.- None of the experiments made showed that the larvæ subjected to a continuous low temperature, even reaching to 18°, will die, although larvæ kept at from 280 to 180 for a time, then revived by warinth, and then restored to the cold temperature almost invariably died. In fact the survival at a continuous low temperature is shown by the following experiment:
June 18, 13 larvæ were dropped in a bit of woolen goods and placed in cold room at a temperature of 31°F. June 29, 29° to 33o. July 11, 28°. Self-registering thermometer showed 18° lowest temperature. All larvæ apparently dead. Five taken out and kept in warm room,
Two moved in fifteen minutes, one in thirty-five minutes, and the fourth in seventy minutes. No. 5 showed no signs of life at this time and was watched no longer.
Larvae with corduroy were kept for many days under observation; at temperatures of 37°, 390, 40°, and 42° were absolutely motionless; at 44°, 45°, 470, and 48° were moving very slightly. Forty-eight degrees was the highest temperature reached, and between April 24 and June 15 there had been no attack whatsoever on the goods. On the latter date all larvæ were removed to warm room, when 20 out of 50 revived.
A parallel experiment on uncovered larvæ showed practically the same result.
THE BLACK CARPET BEETLE (Attagenus piceus). — Adult:— The beetle was found to move at 470 and was motionless at 420.
Larvæ.-Larvæ of this species, which is one of the principal household insects in the South, replacing there Anthrenus scrophularia, were tested both with bits of carpet and in corn meal in which they were found. At 389, 39°, 40°, 42°, and 44° F. they were motionless. At 450 those with meal were motionless, but one of those with cloth was seen to move its legs and head slightly. At 470 and 48° both lots moved, though very sluggishly.
Of those kept with cloth at degrees varying from 38° to 480 from May 6 to June 15 none revived after a “long time” in a warm room, from which Dr. Read made a marginal note, “Don't seem to stand longcontinued cold as well as moth larvæ.” With those in the meal, how. ever, the case was different. They were maintained from May 2 to June 29 at a temperature ranging from 29° to 480. On the latter date they were removed to a warm room and only a few revived after 75 min. utes, but next day all were active.
THE LEATHER BEETLE (Dermestes vulpinus).- Larvae.-At temperatures of 360, 38°, and 3910, motionless; at 40o, 11°, and 45° there was slight motion; at 470 and 48° they were active and feeding.
THE DARK MEAL - WORM (Tenebrio obscurus).- Larva.-At 360 to 420, no movement. At 44° to 48°, slight and weak movements of legs. Pupe.-Two papæ were kept in cold room at from 31° to 480 from May 2 to May 11; were then removed to warm room. One partially transformed May 18, but died, and the other died May 25. This observation has no significance, but is included as the only one made upon pupæ except with the following species:
A CABINET BEETLE (Trogoderma tarsale).-Pupa.-Five pupäe have been kept from May 2 to the date of writing (August 14) at a temperature of from 310 to 44o without apparent change.
Adults.—Ten beetles kept from May 2 to July 2 at a temperature of from 310 to 40. Three died during that time and all remained perfectly inactive without ovipositing.