JOURNAL 



OF 



ECONOMIC ENTOMOLOGY 



OFFICIAL ORGAN AMERICAN ASSOCIATION OF ECONOMIC ENTOMOLOGISTS 



Vol. 6 DECEMBER, 1913 No. 6 



THE RHINOCEROS BEETLE (ORYCTES RHINOCEROS L.) 



IN SAMOA 



By R. \\'. DoANE, Stanford Universily, California 



The following notes are based on studies made by the author in 

 Samoa during May, June and July, 1913. 



The rhinoceros beetle, Oryctes rhinoceros L., has long been known 

 as a more or less serious pest of coconut trees in many tropical 

 countries. It is gradually extending its range and wherever it gains 

 a foothold in a new country its ravages cause much worry and usually 

 great financial loss. 



The island of Upolu, German Samoa, is one of the recent places 

 to suffer from the introduction of this pest. Its presence there was 

 first noticed in the fall of 1910 when the ragged condition of some of 

 the trees near the customs house in Apia caused an investigation to 

 be made. As soon as their characteristic work was recognized there 

 was evidence on every hand to show that the beetles were already 

 well established there. Within a restricted area many of the coconut 

 trees were badly injured and the larvae were found abundantly in 

 decaying wood, manure and other refuse. Just how the beetle was 

 introduced into Samoa will probably never be known, but it is quite 

 likely that young larvae were brought in ^\ ith soil and vegetable refuse 

 packed around the stumps of rubber trees imported from Ceylon. 



Unfortunately systematic attempts were not made to exterminate 

 the pest when first discovered. Certain control measures were adopted 

 but the fight was not carried on vigorously enough to keep the beetle 

 from gradually spreading to all the districts near Apia and later to 

 more distant parts of the island. 



The prevailing northeast trade-wind has been a determining factor 

 in the direction of the spread of the insect, the districts to the wind- 

 ward of Apia showing comparatively little damage. In the other 

 direction practically all of the plantations are more or less affected, 

 the infestation having passed around the end of the island and for 



