THE INTRODUCTION OF SCOLIA MANILAE ASHM. 

 INTO THE HAWAIIAN ISLANDS. 



By F. MuiR, Hawaiian Sugar Planters' Association. 



In July, 1912, the presence of Anomala orientalis (Water- 

 house) was first recognized in the Hawaiian Islands, where 

 it was found injuring the roots of sugar-cane. There are reasons 

 to believe that it was introduced into the archipelago, probably 

 in the soil of potted plants from Japan, more than four years 

 before its presence was discovered. Although in 1912 it was 

 con-fined to a comparatively small area, yet it was too widely 

 spread to hope to exterminate it by drastic measures. As the 

 use of insecticides did not prove any more successful here than 

 elsewhere, it was decided to try and introduce insect enemies 

 known to attack Scarabaeidae in other parts of the world. 



In judging of the probable utility of such enemies, it must 

 be borne in mind that the biological environments of the 

 Hawaiian Islands are very unique. Although the native 

 insect fauna is rich in species of several groups, there are several 

 large groups totally unrepresented. The whole of the great 

 complex of the Lamellicornia is only represented by a single 

 genus of Lucanid^ (Apterocychus) with a few allied species 

 confined to Kauai, the most isolated and north westerly Island 

 of the group. Of the enormous family of Scarabaeidae not a 

 single species is native, and there are good reasons to believe 

 that the few species that are present have been introduced 

 since the advent of the white man. Adoretus temtimaculatus 

 Waterhouse (known locally as the Japanese or rose beetle) 

 was introduced from the Orient about 1896 and is one of the 

 worst garden pests in the Islands, making the growing of 

 roses in the lower and dryer districts very difficult, and spoiling 

 the looks of many of the ornamental shrubs, on account of the 

 ravages of the adult insect. The natural corollary of these 

 conditions is the total absence of all the natural specific enemies 

 of the Scarabaeidae, such as Scotia, Tiphia, Presena, etc., which 

 play an important part in keeping these beetles in check in- 

 other parts of the world; also the absence of those Mutilids, 

 Bombyliids, Rhipiphorids, etc., which are known to attack the 

 above parasites. It is this simplicity of biological environments 



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