54 Flowers and thdr Unbidden Guests. 



Many of these insects had certainly not visited the 

 flowers intentionally, and may have been brought by 

 mere accident into adherence with the sticky peduncles, 

 having been carried there by currents of air, just as 

 happens with the fruits of Compositse, or with grains of 

 sand, which are so commonly to be seen adhering among 

 the insects. A considerable number, however, of the 

 animals had doubtless come in search of nectar, but were 

 such as would have been very unprofitable and unwel- 

 come visitors to /S. nutans, inasmuch as they would have 

 stolen the nectar without bringing foreign pollen to the 

 stigma, and therefore without producing intercrossing.^ 

 The viscid substances are found on the leaves no 

 less frequently than on the stems, and especially on 

 those parts of them over which creeping insects must 



Pag., Oorticaria elongata Gyll., Apion flavipes Fab., Thyamis lurida 

 Sc. ; bugs : Globiceps selectus ; several Aphides ; one Cicada : Delto- 

 cephalus distingue/ndus, and of Diptera : Melanostoma mellina L., 

 Melithreptus menihastri L., Gymnoptemus germanus W., Pipienulus 

 pratorwm Fl., P. Silvaiicus, Mg., Hilara lurida Fll., Gcenosia moUicvia 

 F\l., C. sexnotata Mg., Morinia melanoptera Fell., M, nana Mg., 

 Anthomyia floralis Fll. Ohlorops rufina Zett., Ch. hypostigma Mg., 

 Ch. namta Schrank., Empis hyalipennis, Cyrtoma spuria FU., Phyto- 

 myza affinia Fll., other Diptera again from the genera Ocenosia, 

 Platypalpus, Ceratopogon, Chironomus, several species of Sciara. I 

 have to thank my kind friends von Dalla Torre, Heller, G. Mayr, 

 Palm and Kogenhofer for the determination of the animals men- 

 tioned above, as also of the others mentioned in this treatise. Many 

 of the insects which were found sticking to the peduncles of Silene 

 nutans were so injured that it was impossible to do more than de- 

 termine the genus. 



1 "With regard to Silene nutans see p. 130, § 7, " On the tempo- 

 rary suspension of the functions of individual parts of the ilower." 



