364 EXPERIMENT STATION RECORD. [Vol.88 



There is a wide variation in tlie number of molts, a little more than half of 

 those under observation having molted only 5 or 6 times, about one-fourth of 

 them molting 8 times, and the remaining fourth, 4, 7, 9, and 10 times. It is 

 pointed out that there is also a wide variation in the duration of the larval 

 Instars. 



The duration of the pupal stage, which is passed entirely within the sawdust 

 cell constructed by the borer in its tunnel in the wood, is also quite irregular, 

 varying from 5 to 73 days, with an average of 24 days for the 70 specimens 

 observed. The longevity of the adult varied for the 24 specimens observed 

 from 75 to 222 days. It was found that a single female will deposit from 100 

 to 184 eggs in the course of its life, at an average rate of from 1 to 2.4 eggs 

 per day. 



It is pointed out that the most important control measure is that of keeping 

 the trees in the healthiest condition possible. Trees of which the trunks are 

 badly infested should be cut down and burned as it is practically impossible to 

 save them and they will serve as a source of infestation and a menace to the 

 healthy trees. In some cases the borers may be killed by injecting carbon bi- 

 sulphid into the tunnels and plugging the opening with putty, but this method 

 is impractical where the infestation is severe and well advanced. 



[Report on the banana borer in Mayumba], R. IMayxe {Bui. Agr. Congo 

 Beige. 7 {1916), No. 8-4, pp. 236-239, fig. i).— The curculionid Cosmopolites 

 sordida, the larva of which bores in the trunk, has resulted in a great decrease 

 in bananas in certain regions of Mayumba. Accounts of this pest in Fiji by 

 .Tepson (E. S. R., 35, p. 57) and in Jamaica (E. S. R., 37, p. IGl) have been 

 noted. 



Injurious Biitish weevils, H. Bastin {Jour. Bath and West and South. 

 Counties Soc., 5. ser., 11 {1916-17), pp. 56-81, pis. 8). — The author here brings 

 together in small compass the known facts relative to the life histories of 

 British weevils and notes on the various methods employed in their control. 



Bees and their management, W. Herrod-Hempsall (In Live Stock of the 

 Farm. London: The Gresham Put). Co., 1916, vol. 6, pp. 1-63, pis. 3, figs. 15).— 

 A summary of information on beekeeping. 



The structure and life history of Bracon sp. : A study in parasitism, J. W. 

 MuNRO {Proc. Roy. Soc. Edinh., 36 {1915-16), No. 3-k, PP. 313-333, pis. 2).— 

 This paper deals with an important braconid parasite of the brown pine weevil 

 {Hylobius abietis), the worst insect pest of foresti'y in Scotland, which is 

 thought to be Bracon hylobii. In laboratory work three broods were reared 

 during the summer and no hyperparasites observed. The parasite has been 

 found in nine counties of Scotland, showing a wide and probably general dis- 

 tribution and indicating that it is probably present wherever H. abietis occurs 

 in numbers. A preliminary account has previously been noted (E, S. R., 32, 

 p. 852). 



Italian entomological fauna. — Hymenoptera: Formicidae, O. Emery {Bui. 

 Soc. Ent. Ital., ^7 {1915), No. 1-^, pp. 79-275, figs. 92).— A. synopsis of the 

 Italian species. 



Further investigations on the economic importance of the Gramang ant, 

 P. VAN DER GooT {Medcd. Proefstat. Midden-Java, No. 22 {1916), pp. 120, pis. 

 6; abs. in Rev. Appl. Ent., Ser. A, 5 {1917), No. 7, pp. 273-276).— A report of 

 further studies of Plagiolepis longipes in Java (E. S. R., 35, p. 467), and particu- 

 larly of control measures. An account of the green scale {Coccus viridis) and 

 its natural enemies is appended (pp. 68-91). 



The silverfish or " slicker," an injurious household insect, E. A. Back 

 {U. S. Dept. Agr., Farmers' Bui. 902 {1917), pp. 4, figs. 2). — This supersedes 

 Farmers' Bulletin 681, previously noted (E. S. R., 33, p. 459). 



