ÂTTLAX Papaveris Pehkis 139 



of Peyiiitscii (1) for oiic insect. He ]»ut lice wliicli ]ive<l on iiitlo- 

 resoeiict's of A r a 1> i s s a y i t t a t a ou tli(^ iiiHorc'sceiiccs of a- iiiiiii- 

 ber of other s])ecies of .V r a h i s and saw ,t>'alls (leNclop tliemsehes 

 here to«», and tlie flowers chaiiiic luifh'r the intlnence of tlie liée. Tlds, 

 as a heiiiiininii ot exix'riniental research, is of i^reat importance. For 

 by interferin.^- e\]»eriiiientally we c(»nld trace the influence of a eei'fain 

 gall - ]>roducing substance, ensyni, as it is called, on difïerent plants 

 or i>arts of i)lants. Wlien we considei' the ])lants (as De Vrieb lias 

 develoi)ed aiii]»i\' in his 1 n t r a c e il u I a r e 1* a u g e n e s i s 1889 

 a-nd later in his M n t a t i o ii s t li e o r i e) as consisting out of ele- 

 mental units . wiiicli exist each foi' tJiemselves and ai'c a constant 

 magnitude . hut obey mutually to certain laws of c(»rrelation , it is 

 of great importance . to know how eacli of these units or a grou]> 

 of units belia\(' iindei- tlie infjueiu-e of the same gall-ensym. 



W'e migiit then see, which characters would a[)pear iii oiu^ si)ecies 

 and whicli in aiiother si»ecies of plants. We are still far from a ra- 

 tional investigafion. For this our kiu)wledge has not yet aihaiiced 

 far enough and the experiments to }x*^t foriiuifion of galls on other 

 ])lant species than on thosc^ on which they are usuai . ha\'e failed. 

 We remind the reader of the exiteriments which Beveimnck (L*) made 

 with Rhoditt'.s .ifdifri on 11 o s a <• i n n a m o n e a and r u g o s a. On 

 eithei' sorts of loses eggs were laid , l)ut theiv was no idea of for- 

 mation of galls. 



We tried some foi'ms too, but up till now we had negative re- 

 sults, except in one ease, where we saw the formation of a gall of 

 Khoditcs rosac on a Uosa rugosa on which we had i>ut such 

 wasps. 



Keturning to our Ai(l((.r jKipdrcn's, we tind their galls nu'utioned 

 as ha\ ing been found on different si>ecies of P a p a v e r. l>ut it is 

 questionable, if really the same species of Aiil(Lr is able to ]»roduee 

 galls on all th<»se 1* a ]> a v e i- forms. It is our opinion that we must 

 not conclude to the homology of the aniuuds only from morpholo- 



(1) I'KYKri'scii — Ziii' iitliiologie «1er ClildiantliitMi ciiiij^er Ainliis-mtt-ii. Priiig- 

 sliciias .):iliil). r. wi.Ms. l!«>t. XIII. 1. 



(2) M. W. l)F,YKi{iX('u — Beobachtungen über «lie ersten Entw. [)ha.sen einiger 

 Cyuipiclcii Giilleu. Amsterdam. Joli. Müller 1882. p. 162. 



