AuLAX l'Ai'AVKTUS Peuhis 151 



iiially ai)]>éar, but vvliicli do \n tliis cast- under the intìnence of the 

 A/?/rf.r-larvae. Also tlie .yall differs in this cardinal ])oint , that the 

 •iall-fonnation l)e<iins later. In most cases, as is shown by Beyerixck 

 the tissues form a i»lasteui directly after the eg'ii's are laid, and when 

 the larvae are liatched, the gall is already formed foi- a great part. 



COXCLrSIONS 



1. The species Anltt.r jxipart'ris is subdivided into several ele- 

 mental si)ecies, wliich differ in those characters, that give it faculty 

 to i)roduce galls on (liferent popi)ies. 



'2. This is one of the causes, that the experiments to obtain 

 galls on different ] »hints by one gall-insect, fail. 



o. Tlie female was)» lays her eggs in the tlowerl)uds , which 

 have as yet a bent stalk and are closed and the eggs lie between 

 the se})ta in the central cavity of the ovary. 



4. The eggs are hatched and the larvae feed on the tops of 

 the ovulae and only after some time the tissues change under the 

 intluem-e of the animals to form the gall and gall-chanibers. 



5. In these galls we Hud an exam^de tliat in cells which are 

 at the end of their develoimient and dift'erentiation , there are still 

 latent characters to be activated bv a certain stimulus. 



Mil. ,1. H. VAN i)FAi Vooit'i' was so very kind as to help us with 

 the translation of our study into the English language^ for which we 

 wish here to express our hearthy thanks to him. 



