ON THE UTILIZATION 



I 



.) 



•ttl n 





n be no 



- ,., .ho cavity vatic* pe. .ly in diftient instance,, bat, allowing fox- this, then- 

 "il that icr nombe- effect entrance ••i*^'^ "TT*- 





«. 



■ C 



IT S-to ones. The following are the data regarding this point as recorded of 



' llr of «~ in which the point was specially mveshgated;- 



1 Four voung gall-receptacles were opened shortly after a large emergence of 



insects had taken place from mature ones on the same tree. In all of them 

 the corpses of insects were present packed away among the ostiolar bracts; 



insects had gained access to the cavity; in one a single insect 



two no insects naci g 



had gain* 1 access, but the cavity was still dry; in one twenty insects had 

 entered, the i ivity contained some fluid, the ovaries were evidently enlarged, 



scoDie examination unsegmented, pedicellate ova were found 



on microsc' 

 thin the nucell 



2. A gall-receptacle opened and found to contain the corpses of twenty-four insects 



ut no fluid 



A female receptacle opened fifteen days after insects had been seen to enter 



the osti«»le. Ten corpses of insects present in the cavity, the ovaries 

 enlarged, but no fluid yet present. 



4. Five female receptacles opened. All showed evident general ovarian enlargement. 



One contained a single insect ; one four ; two five ; and one nine. 



5. Four female receptacles with general enlargement of the ovaries opened. All of 



them contained several insects. 



6. A female receptacle with general enlargement of the ovaries contained four insects. 



male receptacle full of fluid and containing about 7,000 enlarged ovaries, 

 including well- developed embryos, showed two insect corpses. 



8. A fi male receptacle with about 12,700 enlarged ovaries, including embryos, con- 

 tained only one insect-corpse within the cavity. 



1 A female receptacle with universal ovarian enlargement contained a single insect. 



10. Six female receptacles with general ovarian enlargement opened. Two contained 



one insect; three two ; and one twenty -two. 



11. One nearly mature female receptacle with general enlargement of the ovaries 



contained three insects with one or two shrunken pollen-grains adherent to 

 them. 



1 2. A female receptacle with general ovarian enlargement contained one insect. 



1 '3. A female receptacle full of fluid and with general ovarian enlargement contained 



four insects 



14. A mature female receptacle full of normal achenes contained one insect embedded 



in the gelatinous coating resulting from the softening of the outer coats 



of the ovaries. 



The above data show clearly that in the case of the female receptacles the results 

 following access of insects are not proportionate to the numbers actually attaining entrance, 

 and that the entrance of a single insect is sufficient to determine general ovarian enlarge- 

 ment and the development of thousands of embryos. The latter fact has been brought out 

 very clearly in certain special cases. In the first of these a receptacle into which a single 

 insect had gained access was used as the source whence materials for sections and dissec- 

 tions of the ovaries at an early stage of enlargement were obtained, and in all cases embryos 



