452 EXPERIMENT STATION RECORD. 



" Tlie insect may be controlled by spraying with the nicotin solutions black- 

 Jeaf 40, Nico-Fiinie liquid, and i\'icoticide, diluted from 400 to 450 times in 

 water, and ar)l>lied at intervals of 11 or 12 days, or somewhat oftener if the 

 temperature in the greenhouse is higher than that at which marguerites are 

 usually kept. The picking of leaves, it would seem, is in most cases neither 

 adequate nor satisfactory." 



A bibliography of the literature relating to this subject is appended. 



Life history of the melon fly, E. A. Back and C. E. Pemberton ( TJ. H. Dcpt. 

 Apr., Join: Agr. Research, 3 {1!HJ,), No. 3, pp. 269-27 4). —This r)aper reports the 

 results of studies of the life history of Bactrorera (Dacus) eueurhitw as 

 worked out by the authors in the Hawaiian Islands, where, next to the Medi- 

 terranean fruit fly, it is tlie most important insect enemy of fruits and vege- 

 tables. Brief accounts of this species by Van Dine (E. S. R.. 18. p. 61) and by 

 Marsh (E. S. R., 25, p. 461) have been previously noted. 



While first I'ecorded in November, 1808, it is said to have been known about 

 Honolulu for many years before. The pest has spread so rapidly that it is now 

 found on all the important islands of the Hawaiian group, and cantaloups and 

 watermelons can not be grown except on new land distant from old gardens. 

 More than 95 per cent of the pumpkin (Cueurhita pciio) crop is annually ruined 

 and havoc is caused among the more resistant cucumbers (Cueiimis sativus). 

 The fly not only oviposits in the fruit but more often — with the pumpkin and 

 squash — in the unopened male and female flowers, in the stem and vine, and 

 even in the seedling itself, especially in seedlings of the watermelon and canta- 

 loup. Entire fields of watermelons have been killed before the plants were 6 

 to 8 in. long by the larvje boring into the taproot, stem, and leaf stalks. At 

 certain seasons of the year nearly all the flowers are affected before they have 

 an opportunity to bloom. In addition to cucurbitaceous crops, which are the 

 favorite hosts, certain leguminous crops, such as string beans and cowpeas, are 

 often badly attacked. When the preferred host plants are scarce even peaches,' 

 papayas, and similar fruits are attacked to a limited degree. 



No satisfactory remedy has as yet been found to prevent the infestation, al- 

 though a small percentage of the crops subject to attack may be saved through 

 covering the young fruit with cloth or paper or, in cases of cucurbits, by bury- 

 ing them in the soil until they become sufficiently large to withstand attack. 



Life history studies are reported in detail in tabular form. During the sum- 

 mer months when the daily mean temi>erature is about 79° F. the eggs hatch 

 in from 26 to 35 hours after deposition, while at a mean temi>erature of 73.6° 

 they hatch in from 52 to 54 hours. The larva passes through three instars; at 

 a mean temperature of about 79° its development is completed in from 4 days, 

 4 hours, to 7 days. At mean temperatures ranging from 71.6 to 79.4° the pupal 

 stage varies from 7.5 to 13 days. Adults, which emerged February 17, were as 

 strong and vigorous 6 months and 14 days later as when they emerged. The 

 majority of the females observed did not mate until fully 25 days after emerg- 

 ing. At mean temperatures averaging 75.5° ovipositiou did not commence imtil 

 one month after emerging but continued for a number of months. Thirty-six 

 is said to be the largest number of eggs secured from a single melon fly in one 

 day. The daily oviposition by 10 flies is recorded. 169 eggs deposited from May 

 31 to August IS by a fly which emerged February 17 and was placed on fruit 

 May 22 being the largest number. 



Observations on the larvae of fleas, A. W. Bacot and W. G. Ridewood [Para- 

 f^itology. 7 {W14), No. 2, pp. 157-175, figs. 6).— This article deals largely with 

 the morphology of flea larvfe. 



Short notes on Anisoplia austriaca and methods of combating it. I. V. 

 Vassiliev {Tnuhj Biliro Ent. [St. Peter.vb.], vol. 7, Xo. 2, ^. enl. ed. {191.',), pp. 



