246 EXPERIMENT STATION RECORD. 



Hosts of insect egg parasites in Europe, Asia, Africa, and Australasia, with 

 a suppleinentary American list, A. A. Gir^vult {Ztschr. Wiss. Inscktenbiol., 

 10 {lUU), Nos. 3, pp. 87-91; 4, pp. 135-139; 5, pp. 175-178; 6-7, pp. 238-240).— 

 This list is arranged on the same plan as that for North and South America, 

 previously noted (E. S. R., 25, p. 852). 



Some factors affecting results in the use of high temperature for the con- 

 trol of insects injuring cereal products, W. H. Goodwin (Jour. Econ. Ent., 7 

 {1914), ^<J. 4j PP- 313-322). — The author reports upon experiments conducted 

 with 13 ditTerent pests which show that moisture is a very important factor 

 when using high tempei*atures for the control of insects affecting cereals and 

 cereal products. He concludes that the practical value of high temperature at 

 48 to 50° C. for the destruction of pests affecting such products is much les- 

 sened when the heated atmo.sphere contains moisture greater than 40 to 50 per 

 cent. Oven experiments demonstrate that 50 to 55° kills all stages of cereal 

 insect pests if they are actually subjected to this temperature for one to two 

 hours. " In practical work, moisture conditions are extremely important and 

 must not be overlooked, as failure to obtain the necessary temperature is often 

 due to lack of sufficient radiating surface to overcome the excessive moisture 

 conditions. Because of the more rapid radiation obtained, the use of steam at 

 50 to 60 lbs. pressure will give results superior to those gotten with 8 lbs. pres- 

 sure with one-fourth more of radiating surface." 



The destruction of underground pests, E. Molinas {Prog. Agr. et Vit. {Ed. 

 VEst-Centre), 35 {1914), No. 12, pp. 374-S78; abs. in Rev. Appl. Ent., 2 {1914), 

 Ser. A, No. 6, pp. 362, 363). — The author calls attention to the work of Dumas 

 and others with potassium sulphocax'bonate as an insecticide. Through the 

 action of the carbonic acid contained in the air and in water, potassium sulpho- 

 carbonate, which is produced commercially in the form of a dark red solution 

 containing 14 to 16 per cent sulphid and 18 to 20 per cent of ix)tash, slowly 

 decomposes and resolves itself into carbon bisulphid and sulphureted hydrogen, 

 both of which gases are insecticides, and a residue, potassium carbonate, which 

 can be used as a fertilizer. Potassium sulphocarbonate is said to have an 

 advantage over carbon bisulphid in that it acts more slowly and for a longer 

 time, and that it entirely impregnates the mass of soil. One part of the com- 

 mercial solution diluted in 100 parts of water, both by volume, and the liquid 

 poured from a watering can in such quantity as to insure adequate penetration 

 kills slugs, cutworms, earthworms, white grubs, longicoru larvae, and millipedes. 



Tulips and carnations are not affected by a 1 per cent solution, and even 2 

 per cent may be used. Only when a 5 per cent solution is employed do carna- 

 tions begin to suffer. The cost of potassium carbonate solution is not very 

 high and its manurial value may also be deducted. See also the work by Bour- 

 cart, previously noted (E. S. R., 29, p. 341). 



Soil fumigation, J. A. Hyslop {Jour. Ecvn. Ent., 7 {1914), No. ^, pp. 305- 

 312). — This discussion relates to soil fumigation work conducted by the Bureau 

 of Entomology of this Department during the season of 1913. It is claimed 

 that the work has shown (1) that sodium cyanid will not permanently injure 

 the soil; (2) that it can not be api^lied while crops are on the land nor imme- 

 diately prior to seeding; and (3) that it will kill wireworms. 



The food of the earwig (Forficula auricularia) as shown by the contents 

 of its crop, G. LusTNEE {Ccntbl. Bakt. [etc.], 2. Aht., 40 {1914), No. 19-21, pp. 

 482-514; abs. in Rev. Appl. Ent., 2 {1914), Ser. A, No. 9, pp. 546, 5^7).— The 

 author summarizes the literature on the subject and reports upon examina- 

 tions made of crop contents. 



Examination of several lots, compi'ising 162 earwigs, have led to the conclu- 

 sion that they are omnivorous feeders. Normally they feed on dead plants and 



