CHAPTER VI. 



FLOWERS AND THEIR UNBIDDEN GUESTS. 



It is a matter of very common 

 Perforation of Flowers. , ,. ., , "",. 



observation that many of our flow- 

 ers are perforated, and that insects obtain nectar without 

 going to the proper sources. The be autiful c olors and ex- 

 quisite contrivance5^fe-f©adBreS~inoperative because of TEese 

 perforations. The subject has been treated by Darwin i 

 and others ^. Mr. Jack^ has also recentlj'^ contributed a 

 short note on this subject in which he cites a number of 

 interesting cases. The chief perforators are bumble bees 

 (Bombus), carpenter bees {Xylocopa) and wasps (Vespa-) 

 Hive bees and birds have also been observed. Why should 

 insects perforate flowers ? Darwin believes that, as a gen- 

 eral rule, flowers are onl}' perforated when they grow in 

 large quantities close together; for he found in a garden 

 where Stachys cocdnea and Pentstemon argutus were 

 growing in large numbers, every flower was perforated, but 

 at some distance from these was a small stock of Stachys 

 cocdnea the flowers of which were much scratched, show- 

 ing that they had been visited by bees, although not a single 

 flower was perforated. The same thing was noticed on a 

 small stock of Pentstemon, growing in the same garden. 



1 Ordss aud self-fertilizatiOQ. Mueller, L, C, etc, 



2 L. H. Pammel; Trans., St. Louis Academy of Science, vol. X, pp. 246-277i 

 A biblography is given in this paper. 



3 Garden and Forest. Vol. V; p. 29. 



