
at ee 
From the submergence tests of larvae of fruit flies (Anastrepha) 
made at Panama, Canal Zone, by James Zetek, "it is evident that infested 
fruits, if dumped into Gatun Lake (for example) can float around for 
days and finally reach shore, and at least some of the larvae can reach 
earth and pupate." 
A third shipment of adult parasites, consisting of 600 Diachasma 
tryoni Cam. and 100 Opius humilis Silv. sent by A. C. Mason, Honolulu, 
T. H., has been received by Prof. Harry S. Smith, at the Citrus Experiment 
‘Station, Riverside, Calif. Mr. Smith reports that the insects had parasi- 
tized the walnut husk maggots (Rhagoletis completa Cress.) in his labora-— 
tory and are developing satisfactorily in their new hosts. "The only 
question now," Mr. Mason says, “is whether they can hibernate in Cali- 
fornia and be able to synchronize their life history with that of the 
host." 
R. H. Marlowe, of the toxicological unit, Honolulu laboratory, re- 
ports as follows on the lethal effect of distilled and sea water on, and 
pupation of, larvae of Ceratitis capitata Wied.: "The effect of distil-~ 
led water on the pupation of larvae is influenced almost entirely by 
depth. The influence of sea water on the per cent pupation is affected 
not only by depth but also by density, and the probable factors of vol- 
ume, liquid-air surface exposed, and the biochemical reaction of the salt 
solution no doubt exert some influence on the lethal effect of the solu- 
tions on the larvae. The effect of sea water as to drowning is much great— 
er than that of distilled water, but the influence indirectly on the 
mortality of the pupae is not so great. * * * In distilled water. the 
larva swells; in sea water it shrinks. * * * Total per cent pupation is 
greater in distilled water (55 per cent) than in sea water (35.9 per 
cent). eA certain percentage of adult Ceratitis capitata will emerge, not 
only from larvae that pupated during eight hours' submergence in distilled 
and sea water at certain depths, but also from larvae pupating upon re- 
moval from the solutions." 
0. C. McBride, Honolulu, reports on a heat-sterilization experi- 
ment made on pineapple to determine the heat distribution and kill of 
mealybugs when the room was packed full. Thirty thousand plants were 
used in the experiment. Mr. McBride says, "Air and temperature records 
were made by means of thermocouples placed at twelve different points 
in the room * * * It requires 4 1/2 hours to bring the inside plant ten- 
peratures from 26.5° C. to 50° C. When the plants reached 50° C., the 
steam was shut off, the fan reversed, and the plants left in the room 
Over night. One hundred and twenty plants, as checks, selected at ran— 
dom, gave a count of 2,081 mealybugs, alive. A random selection of an- 
other 120 plants after heating gave a count of 117 live mealybugs, or a 
kill of 94.38 per cent. Working with smaller samples and holding the 
temperature for one-half hour after the inside plant temperature reached 
50° C., we secured 100 per cent kill. On the basis of experiments to 
date, it appears that the heat-vapor saturation method can be satisfac-— 
torily employed for the control of mealybugs on pineapple planting stock." 
