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old from the egg waen captured, and their lives were probably short- 

 ened bj' the unusual conditions and experiences to which they were 

 subjected. This long life is of very considerable importance in con- 

 sidering the value of these insects as exterminators of the San Jose 

 scale. Their fecundity is also considerable, as indicated by the actual 

 securing of some 200 eggs from an imported specimen and under 

 unfavorable conditions, not counting the loss of a good many eggs. 

 It is not improbable, therefore, that a single female may be the parent 

 of at least 600 young, and the period of usefulness of an individual 

 may extend over twelve months. 



The egg is normally concealed under an adult female scale. In other 

 words, the beetle selects a suitable scale, drags out the female scale 

 insect, and either eats it while ovipositing or drops it, turns about and 

 thrusts the ovipositor under the slightly lifted edge of the scale, and 

 in two or more minutes deposits a single egg. This habit of oviposi- 

 tion seems to be peculiar to this species. It was found later on, when 

 the beetles became more numerous, and especially during the period 

 when the old female San Jose scales were not so abundant, and the 

 trees were covered with young scale insects, that other locations would 

 be chosen bj- the beetle for oviposition, namely, under the loose edge 

 of bark or like situation, or more rarely eggs would be deposited 

 exposed on the bark. 



Later in the summer other large cages were built over some pear 

 trees infested with San Jose scale. In all five such cages were built, 

 each of the four later ones including two pear trees about ten years of 

 age but cut back to small size. In these cages the beetles throve 

 wonderfully well. One cage in which two individuals, a male and a 

 female, were placed in May, was swarming with beetles by the middle 

 of July, and more than 100 beetles were taken from it for distribution 

 elsewhere without greatly lessening the stock. 



The multiplication of the beetles at this stage was fairly satisfactory, 

 not so much so, however, as it should have been if the experiment had 

 not been interfered with by the presence of certain predaceous insects 

 to be considered later, notably the wheel bug, two species of praying 

 Mantis, lace-winged fly larva, and the larva of Adalia hipuncfata, it 

 being almost impossible to free these rather large cages from all of 

 these insects. In spite of all the drawbacks, however, the beetles have 

 multiplied to exceed 500 specimens, perhaps 1,000, by the 1st of July 

 from the single overwintered pair, but one of which was presumably 

 a female. 



We are making arrangements to ship these beetles to the entomolo- 

 gists and State experiment stations this summer and fall, and we hope 

 to establish this ladybird in the eastern United States. It feeds vora- 

 ciously on the San Jose scale and on the Diaspis. The larvae are eating 

 all the time, and the rate of multiplication is such that five annual 

 7796— No. 37—02 6 



