24 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 82 



a constituent of all the oils found to be distinctly attractive. Tests were 

 made of a series of the preferred food plants, and in all cases these 

 plants contained geraniol in varying quantities. The present writer 

 has seen no report by a chemist concerning the last statement ; but as 

 regards fruit. Power and Chesnut (6i) found geraniol in apples. They 

 used only the parings of the Mcintosh, one of the most fragrant 

 varieties of apples, and say that geraniol, either in the free state or in 

 the form of esters, is probably contained in varying c^uantities in all 

 the numerous varieties of apples, although to the greatest extent in 

 those which possess its distinctive odor. Power and Kleber (62) tell 

 us that the two oils, one from sassafras bark and the other from 

 sassafras leaves, are fundamentally different in regard to their chemi- 

 cal compositions. Oil from sassafras bark contains eugenol but no 

 geraniol, while oil from sassafras leaves contains geraniol but no 

 eugenol. There are also other differences. The fact that Japanese 

 beetles were observed to be fond of sassafras leaves led to tests in 

 which the oil of sassafras was used ; after learning that oil from 

 sassafras leaves contains geraniol it was only natural to continue 

 using geraniol in bait mixtures. 



A popular impression is that Japanese beetles are fond of geraniums 

 and that our supply of geraniol comes from these plants, but this is 

 far from the truth. Ballou (4) informs us that these beetles do feed 

 upon the flowers and to a limited extent upon the foliage of cultivated 

 geraniums (Pelargonium spp.), but with deleterious effects to them- 

 selves, because this food is toxic to them. Most of our commercial 

 supply of geraniol is said to be derived from the oil of citronella, 

 but in perfumery much of it also comes from the oil of palmarosa or 

 Turkish geranium. Geraniol also occurs in the oils of lemon-grass, 

 geranium, rose, sassafras leaves, and other essential oils. 



(n) BAITS FOR OTHER BEETLES 



Since 1916 it has been reported in numerous publications that cer- 

 tain sugarcane cockchafers in Australia can be attracted by odors 

 from various chemicals and by the aromas distilled from their food 

 plants, but it seems that so far no practical results have been obtained. 

 Other reports by Jarvis (34, 36), however, indicate that poisoned 

 baits have a practical value in helping to control the grubs of these 

 beetles. 



For years it has been known that poisoned -bran baits are of con- 

 siderable value against the common May beetles and more recently 

 Yickery and Wilson (92) used a bait consisting of 20 pounds of 



