119 



FLOWERS AND THEIR UNBIDDEN GUESTS. 



In the September number we consid- plants, and it may be noticed that it is apt 

 ered flowers and their invited guests, that to increase in amount and prominence 

 is the insects useful in carrying pollen, towards or within the flower cluster. Some- 

 The very things which attract useful in- times the flowers themselves are hairy out- 

 sects to flowers are attractive also to use- side,andinthecaseof the trailing arbutus, 

 less insects. For example, nectar in a whose flowers close to the ground are in 

 flower seems just as desirable to an ant special danger from creeping insects, the 

 as to a butterfly, but the ant is a creeping flowers are filled with a fluffy mass of 

 insect and would be likely to lose the hairs. In our illustrations, the wild co- 

 pollen in passing from one plant to an- lumbine, the Oswego tea, the sunflower, 

 other. If useless insects found free ac- and the ox-eye daisy are all hairy plants, 

 cess to flowers and carried off their food and difficult for ants to climb. In the 

 supplies, the useful insects would soon September number are illustrations of the 

 stop visiting them. It is of great advan- mallow, the lady's slipper, and the New 

 tage to flowers, therefore, to have some England aster, all of which are hairy and 

 means of warding off the creeping in- discouraging to ants. 

 sects. It must not be understood that all An interesting fact in connection with 

 plants are equally successful in this mat- the wild columbine may be noted. The 

 ter, or that any plant is always successful, nectar is deposited in the knob-like bot- 

 but there are certain things which seem torn of the long tubular spurs, and the en- 

 to hinder or discourage the approach of trance is so carefully guarded that only 

 creeping insects to flowers. ' a long and slender proboscis, like that of 



Perhaps ants may be taken as the best a moth or a butterfly can reach the nectar, 



illustration of the insects whose visits are The bumblebees, however, have learned 



discouraged by flowers. They are very this fact, and bite through the tips of the 



much attracted to the food supplies in the spurs and steal the nectar. As a conse- 



fiower, especially the nectar, and are quence, the wild columbine is said to be 



among the most intelligent of insects, little visited by the proboscis-bearing in- 



often overcoming the most serious ob- sects, and its pollination is seriously in- 



stacles. They will be considered in this terfered with. 



paper, therefore, as the insects which are Sticky excretions. Some plants have 



seeking the nectar and pollen of flowers the power of excreting upon their surface 



without invitation. A charming little a sticky substance like mucilage. This 



book upon this subject has been written mucilage may be produced by hairs, 



by Kerner, and translated into English, which are then called "glandular hairs," 



under the title which appears at the head or it may appear directly on the surface 



of this paper. It is in this book that the of the plant. When ants or other insects 



chief obstacles to such unwelcome guests try to cross such a barrier they are not 



as ants are clearly stated. merely stopped but caught. Upon 



Hairs. One of the most common ob- "glandular" plants it is very common to 

 stacles to ants is a barrier of hair. For see small insects stuck fast, and it is more 

 some reason, ants dislike to cross such a than probable that the nourishing ma- 

 barrier. Travellers in tropical countries, terial of their bodies is digested and ab- 

 where ants abound, tell us that a hair rope sorbed by the plant. In this way the plant 

 laid around a tent is a very effective bar- not merely stops the insect, but catches 

 rier against the invasion of armies of ants, and devours it. 

 Hair is very commonly found upon A very common illustration of such a 



