374 



appear at regular intervals, or at definite seasons. Usually a crop 

 planted at any time from November to February, the season during 

 which the radish succeeds best, will escape the ravages of this pest, 

 though this is not certain. Spraying with lead arsenate has been 

 attended with fair results. The larva of a small moth sometimes 

 destroys the crop of Lima beans by feeding mthin the pod, when 

 nearly mature. A small leaf -miner attacks the leaves of both Lima 

 and string beans, but apparently has little influence on production. 



Back (E. A.) & Pemberton (C. E.) Life-History of the Mediterranean 

 Fruit-Fly from the Standpoint of Parasite Introduction. — Jl. Agric. 

 Research, Washington, D.C., iii, no. 5, L5th February 1915, 

 pp. 363-374, 2 plates, 6 tables. 



The failure of Silvestri to introduce Tetrastickus gijfardii into Hawaii 

 is ascribed to the short life of the parasite and its habit of ovipositing 

 in either the egg or young larva of Ceratitis ca'pitata. The writers 

 have developed simple methods of rearing Ceratitis capitata, which 

 have resulted in the prevention of many failures in connection with 

 the introduction of parasites, since they provide a means of making 

 available the various stages of the fruit-fly for the rearing of new 

 generations of parasites. The usual method of obtaining a colony of 

 fruit-flies consists of placing infested fruit over sand in some securely 

 screened container. The simplest way is to use a contrivance which 

 will keep the fruit free from the sand and at the same time bring the 

 emerging larvae to a central point. This is a funnel of galvanised 

 iron, held in a suitable support, mth a half-inch mesh screen at the 

 bottom. Larvae, as they emerge, work their way downwards into 

 the container below. This arrangement works well with various 

 fruits. The old method of using a shallow box, covered with a varying 

 depth of sifted sand, required a great deal of time ; the writers now 

 use a frame 6 by 3 by 3 feet, a figure of which is given. The old box 

 system is useful when it is desirable to keep separate pupae from small 

 lots of fruit from different localities. The sand below is kept dry and 

 can be easily sifted to obtain the pupae. The adults generally emerge 

 early in the morning during warm weather ; for food, fruit juices of 

 any kind may be given, or water sweetened with pine-apple juice or a 

 mixture of water and finely divided papaya. When not rec[uired for 

 oviposition, the flies can be kept alive by suspending a juicy fruit 

 within the jar. Fed in this way and kept at a temperature of 58°- 

 63° F., adults have been kept alive for six months ; when the average 

 temperature is 76°-79°, the longevity is only about three months. 

 Males attain sexual maturity in about four days after emergence, 

 females in about 6-8 days. The time of oviposition after emergence 

 varies with the temperature ; at a mean temperature of 74°, eggs are 

 laid in 7-8 days. The females lay small batches of eggs quite regularly 

 throughout life. 



Differences exist between the habits of the adults of Badrocera cucur- 

 bitae, Coq. (the melon fly), and those of Ceratitis capitata. The melon 

 fly adult lives more than six months, exhibits no sexual activity for 

 20-25 days after emergence, and flies only at sunset. The female is 

 more irregular in her habits of oviposition, but a larger number of 

 eggs are laid at one time. Eggs of C. capitata can be obtained by 



