660 BXPEEIMEin' STATION BECOBD. [VoL 36 



countered during the first half of the brood-rearing season than during the 

 second half, it may be produced by inoculation at any season of the year that 

 brood is being reared. " It occurs among bees in localities having as wide a 

 range of climatic conditions, at least, as are found in the United States. The 

 course of the disease is not greatly affected by the character or quantity of 

 the food obtained and used by the bees. Larval remains recently dead of the 

 disease prove to be very infectious when fed to bees. Dead larvje which have 

 been in the brood comb more than one month are apparently noninfectious. 

 Colonies possess a strong tendency to recover from the disease without treat- 

 ment. 



"The virus of sacbrood suspended in water and heated to 138° F. (59° C.) 

 was destroyed in 10 minutes. Considering the varying factors which enter 

 into the problem, the minimum temperature necessary to destroy this virus 

 when applied for 10 minutes should be found at all times to lie somewhere 

 between the limits of 131 and 149° F. When the virus of sacbrood is sus- 

 pended in honey it may be destroyed by heating the suspension for 10 minutes 

 at approximately 158°." 



The virus resisted drying at room temperature for approximately three 

 weeks. It was destroyed by the direct rays of the sun in from four to seven 

 hours when dry, when suspended in water in from four to six hours, and when 

 suspended in honey in from five to six hours. \i\Tien suspended in honey and 

 shielded from direct sunlight it remained virulent for slightly less than one 

 month at room temperature during the summer. The virus was destroyed in 

 approximately five days in the presence of fermentative processes taking place 

 in 10 per cent sugar solution at room temperature. 



" In the presence of fermentative processes going on in 20 per cent honey 

 solution at outdoor temperature the virus of sacbrood was destroyed in approxi- 

 mately five days. In the presence of putrefactive processes the virus remained 

 virulent for approximately 10 days. The virus will resist 0.5 per cent, 1 per 

 cent, and 2 per cent aqueous solutions of carbolic acid, respectively, for more 

 than three weeks, 4 per cent being more effective. Neither carbolic acid nor 

 quinin as drugs should at present be relied upon in the treatment of sacbrood. 



" Varying factors entering into many of the problems discussed in this paper 

 tend to vary the results obtained. In such problems the results here given 

 must be considered from a technical point of view as being approximate only. 

 They are sufllciently exact for application by the beekeeper, but to insure the 

 destruction of the virus in practical apiculture the time element indicated from 

 these experiments as sufficient should be increased somewhat." 



Descriptions of seven new species of red spiders, E. A. McGkegob {Proc. 

 U. S. Nat. 1/tw., 51 (1917), pp. 581-590, pis. 7).— Six species of Tetranychus and 

 one of Tetranychina are here described as new to science. Of the former, two 

 are from South America and four from North America. Tetranychus ilictis dis- 

 colors the leaves of American holly, T. icillamettei injures at times the appear- 

 ance of the western white oak, and T. monticolus saps the vitality of the large 

 huckleberry of the Cascade region. 



A case of infestation with Dipylidium cajiinum, Makia P. Menuoza-Guazon 

 [PhUippine Jour. Sd., Sect. B, 11 {1916), No. 1, pp. 19-31, figs. 3).— The author 

 records the finding of this canine tapeworm in an infant. 



FOODS— HITMAN NUTRITION. 



Studies on the digestibility of the grain sorghums, C. F. Langwobthy and 

 A. D. Holmes (U. S. Dept. Agr. Bui. 470 (1916), pp. 5i).— This bulletin reports 

 data regarding the digestibility of the grain sorghums, dwarf kafir corn, 



