ANTS AND GREEN BUG 20 



by a number of different species of ants, but there is, as 

 far as we are aware, no record of the scales being in any 

 way protected by any of these ants. Several planters 

 have, it is true, reported that they have seen the green 

 bug carried by the large red tree ant {Oecophjlla smarag- 

 dina) but where they carried them and what they did 

 with them no one had observed. 



This question of the relationship between ants and 

 green bug has received a great deal of attention from 

 workers in Java. Koningsberger and Zimmermann^ were 

 unable to observe the transference of green bugs through 

 the agency of ants and at the same time established the fact 

 that the green bug is able to live and multiply for a long 

 period without being visited by ants at all. Keuchenius" 

 has studied particularly the relationship between the two 

 ants, Oecophylla smaragdina and Plageolepis longipes, 

 and green bug. He comes to the conclusion that, of 

 these, the latter was useful rather than harmful as it 

 neither transfers the green bug from place to place, aids 

 its development in any way nor destroj^s its natural 

 enemies. On the other hand, he considers that this ant 

 plays a role in the spread of the fungi to be described 

 later which form one of the most important checks to the 

 pest ; according to this author the ant also reduces the 

 amount of sooty moulds by decreasing the quantity of 

 honey dew upon which these fungi grow. On the other 

 hand, he concludes that the large red tree ant (Oecophylla 

 smaragdina) is harmful in coffee estates in that it aids in 

 the development of green bug and protects it from its 

 enemies. 



The most careful series of observations and experi- 

 ments which have been carried out on the subject of 

 green bug and its associated ants are those of van der 

 Groot.^ The second of his papers is largely devoted to 

 experiments on the relationship between two ants {Plageo- 

 lepis lo7igipes and Dolichoderus hituherculatus) on the 

 one side and green bug on the other. His conclusions 



* Koningsberger and Zimmermann, loc. cit, Part II, p. 14. 



"^ Keuchenius, Onderzoekingen en beschouwingen over eenige 

 schadelijke Schilduizen van der Koffie Kultuur op Java, 1915, p. 37. 



* van der Goot, Over de Biologie der Gramang-mier (Plagiolepis 

 longipes, Jerd.). Med. van bet Proefstation Midden-Java, No. 1, 1915, 

 and Verdere Onderzoekingen omtrent de oeconomicbe Beteekenis der 

 Gramang-mier, Med. van bet Proefstation Midden-Java, No. 22, 1916. 



