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While the leaf insects kill the young shoots of lantana they" 

 are also, though indirectly, responsible for the periodical 

 heavy crop of lantana flowers. It is a well known fact that 

 plants and animals are most prolific when their chances for 

 life are reduced. This phenomenon is accounted for by the 

 law of perpetuation of the species, i. e., every living being 

 feels the instinctive impulse of helping to perpetuate its kind 

 and, when disease or want of nourishment threatens its exist- 

 ence it turns all of its available vitality toward reproduction. 

 Fruit trees upon a deserted farm where they are neither fed 

 nor otherwise attended to are known to produce heavier crops 

 of fruit than their neighbors, upon an adjoining lot perhaps, 

 living in opulence. In order to hasten the flowering of a 

 plant horticulturists take advantage of this indomitable law 

 and either root-trim those plants severely or plant them in 

 small receptacles. To return to lantana we see that no sooner 

 is a crop of leaves produced than it is immediately stripped. 

 The repeated defoliation evidently so shocks the plant that it 

 feels in danger of extermination. To save itself from such a 

 calamity it concentrates all its available vitality upon repro- 

 duction. The plant, of course, does not reason but it does fol- 

 low out the course laid down for it by nature. This over- 

 production of flowers is in itself therefore, an indication that 

 the plant is suffering. As to the seed crop, I believe that our 

 flower and seed insects will permit but little of it to mature. 

 To all appearances lantana looks now practically doomed. 

 Very few lantana plants are as healthy and vigorous today as 

 they used to be. 



The introduction of insects to check the spread of a plant 

 has, to my knowledge, never before been tried anj^where in 

 the world. Mr. Koebele is the pioneer worker in this line and 

 judging by the marvelous results already attained, the credit 

 to which he is entitled for what he has accomplished cannot 

 be given him in more adequate form than by pointing out the 

 difference between lantana on Hawaii as it was and as it is at 

 present. He is moreover to be congratulated on the strict 

 business-like manner in which these insects confine their work 

 to lantana. 



