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BULLEO^IN 1357, tJ. S. DEPARTMENT OF AGRICULTURE 



Observations on the process of egg deposition by two beetles con- 

 fined in one vial at 2 p. m. were as follows : While seeking a place 

 to deposit eggs the beetles, moving their heads with a rocking motion, 

 touched or " measured " the surfaces of crevices or depressions in 

 the cork alternately with the tip of each antenna, and then tried 

 them out with the tip of the ovipositor slightly extended, moving 

 rapidly from one to another. These two individuals were then placed 

 in separate vials with a small piece of dry and crumpled leaflet. One 

 adult ran nervously about for a time, while the other on finding the 

 leaf settled immediately and began to oviposit. 



Considerable time was spent in preparing a resting place for the 

 eggs. After the long, flexible ovipositor had been inserted, a thin 



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Fig. 7. — Egg mass of the strawberry rootworm on portion of dead leaf, showing develop- 

 ment and characteristic wall which sun-ounds each egg mass. Enlarged 



transparent fluid was secreted at its tip in tiny droplets, and then 

 spread or brushed over both surfaces of the depression with two 

 hairy palpuslike projections of the ovipositor. Twelve minutes were 

 spent preparing the surface and four minutes in forming that por- 

 tion of the wall against which the eggs were to be placed. A tiny 

 droplet of the thin fluid preceded and another followed each egg 

 as it was ejected from the ovipositor, and an interval of about two 

 minutes elapsed between the ejection of each egg. The egg was 

 placed with the help of the palpuslike br\ish, which at the same time 

 spread some of the fluid over the egg and in the spaces around it. 

 When all the eggs had been placed the beetle constructed a wall 

 (fig. 7) to surround the egg mass by secreting a second fluid, which 



