. Sacbrood. Bees. SAOBEOOD. 37 RESISTANCE OF SACBROOD VIRUS TO DRYING AT ROOM TEMPERATURE. In the experiments made for the purpose of determinmg the amount of drying which the virus of sacbrood will withstand, larvse recently dead of the disease were used. These are crushed, strained through cheesecloth, and the crushed mass poured into Petri dishes (fig. 32) to the extent of a thin layer for each dish, the material in each being the crushed remains of about 30 larvae. These are placed in a drawer, shielding the larval material from the Hght. The drying then pro- ceeds at the temperature of th
. Sacbrood. Bees. SAOBEOOD. 37 RESISTANCE OF SACBROOD VIRUS TO DRYING AT ROOM TEMPERATURE. In the experiments made for the purpose of determinmg the amount of drying which the virus of sacbrood will withstand, larvse recently dead of the disease were used. These are crushed, strained through cheesecloth, and the crushed mass poured into Petri dishes (fig. 32) to the extent of a thin layer for each dish, the material in each being the crushed remains of about 30 larvae. These are placed in a drawer, shielding the larval material from the Hght. The drying then pro- ceeds at the temperature of the room. This temperature varied greatly from day to day, sometimes being as high as 93° F. (34° C). At intervals, reckoned in days, after the preparation of the virus, colonies are inoculated. An aqueous suspension is made of the drying larval content con- tained in a Petri dish. This is added to sirup, and the sirup suspension is fed to a healthy colony gave the following results:. Fig. 32.—Open Petri dish. One-half ot Petri dish, either top or bottom. (Original.) The experiments Table IV.—Resistance of sacbrood vines to drying at Date of inoculation. Time of drying. Results of Inoculation. Aug. 8, ,19W. Sept. 6,1915. July Sept. 28,1915 Jtily6, Sept. Sept. 27,1915, Oct. 9, July 29,1915. Septs, 1915. Do May 22,1915. Do 3 days 7 days 13 days 16 days 18 days 20 days 22 days 26 days 28 days 28 days 35 days 45 days 7 months 12 days 7 months 21 days Sacbrood produced. Do. Do. Do. Do. Do. No sacbrood produced. Do. No. Do. Do. Do. Do. Do. From the results recorded in Table IV it will be noted that the virus of sacbrood in the experiment referred to withstood drying at room temperature for approximately three weeks. The inoculations made during the third week indicated, by the re- duced amount of sacbrood produced, that much of the virus had already been destroyed. Obtaining negative results from the use of larval materia
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