348 



So in miscelianeous breeding the percentage of males was 3,78%, 

 in individual breeding (last table) it was 4.35%. T attach more value 

 to the former percentage because it was got from a greater number 

 of specimens. 



The last table shows that only certain eggmasses gave a great 

 number of males, No. 63 (15) and No. 108 (11) but in many cases 

 only very few males came out, or nothing else but females. 



The females being very abundant, the reproductive power of 

 Phanurus has grown exorbitantly strong, Mr. 1'. van der Goot having 

 showu that parthenogenetic propagation is very effective. 



Probably this is the cause that Phanurus in Java is such a very 

 effective parasite on Diatraea, whilst Formosau Phanurus contains a 

 smaller number of females and therefore occurs only in a much 

 smaller quantity in that islam I. 



III. Number of eggs of the grey borer, Grapliolitha schistaceana Su., 



that were found in the investigated cane field in Pasoeroean. (Each 

 eggmass of Grapholitha only contains 1 or 2 eggs.) 



1015. 



Kind of 



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Total. 



1915. 



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Total. 



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