170 



parallels. During that period the lower zone — =i. e., the agi'i- 

 cultural area below 1500 feet elevation — has been remade from 

 the fannal, as well as from the agricultural point of view. Xew 

 plants, new conditions, new insects have been introduced and in 

 many cases encouraged to occupy the land. In the majority of 

 cases their natural enemies have not followed the insect pests 

 that have come to these shores. One of the results of this has 

 been that many agricultural plants and domestic animals are 

 almost without protection from their natural enemies. The 

 speaker for this reason has repeatedly urged that the intro- 

 duction of birds into Hawaii will become of more and more 

 economic importance. 



In this connection, an instance of the condition existing 

 hero may be of interest. In two hours collecting I was able to 

 gather from a patch of sweet corn, a rod square, specimens of 

 seven orders, representing twenty-nine families and thirty-nine 

 species of insects. Fourteen species were directly injurious to 

 vegetation, six doubtfully so, while live were known to be 

 beneticial and four both beneficial and injurious by turns, 

 while the remaining ten were of no known economic importance. 



That similar conditions exist with reference to a nuud^er 

 of the crops grown here in a small way is well known. That 

 these pests will- continue to multiply to the limit of their food 

 supply unless natural enemies are introduced is not disputed. 

 That the native birds are vanishing and, as a class, are now. of 

 little importance to agriculture is shown by a reference to their 

 habits and their weakened condition, both in numbers and 

 species. In the eleven orders of birds represented in Hawaii 

 (two of which have been introduced) there are, all 

 told, not more than one hundred and thirty-two species. Of 

 that number sixty are sea or marsh birds or rare accidental 

 visitors. Thirty-one of the remainder are extinct or too rare 

 to figure in any w^ay in the economic ornithology of even the 

 native forests. Twenty-one species belonging to ten genera are 

 of more or less economic importance. Of this meager list the 

 ])lovei'. the hawk and the owl are non-passerine, so that the 

 eighteen passerine native forest dwelling birds are representa- 

 tives of seven genera. Aside from the w^ork they do in the na- 

 tive forest, they do not count as factors in the struggle against 

 insects, and there is no reason to suppose that they should, 

 since by nature they all belong to the deep forests of the higher 

 elevations. The few (nine) species introduced are of far more 



