G 



Judging from observations made by me on otber imported in- 

 sects, to the rate of increase of which I have paid special at- 

 tention, I should consider that the leaf-hopper was introduced 

 two or three years prior to 1900; but that until 1900 it was not in 

 such numbers that it would be likely to come under the observa- 

 tion even of an entomologist, except by the merest chance. It is 

 t'"ue that some plantation managet s think the leaf-hopper has been 

 present on their plantations for many years, but this is certainly an 

 error of identification. During six years' continuous collecting, 

 from 1892 to 1897, when I formed a large collection of leaf-hop- 

 pers of many species and from every island, I never met with 

 a single individual of the present pest. 



It is incredible that a species which is always gregarious, which 

 produces on the cane the most obvious and characteristic outward 

 signs of its presence, and which, when mature is readily attracted 

 to the lights, should have entirely escaped my notice. Then, again, 

 it was one of the first species noticed and collected by me on my 

 return to active field work in 1900. In the early days of my col- 

 lecting here an allied species of leaf-hopper was known to me to 

 frequent the cane-fields iu small numbers, and this would cer- 

 tainly not have been distinguished from the present pest except 

 by a more careful comparison than a non-entomologist would be 

 likely to make. To sum up, it can be stated most positively that 

 the present leaf-hopper attack is due to a pest comparatively re- 

 cently introduced into the islands and not by one of old standing, 

 which has suddenh' become injurious, as some are inclined to 

 think. 



THE HAWAIIAN LEAF-HOPPER, AN AUSTRALIAN SPECIES AND NOT 

 IDENTICAL WITH ANY OF THE HITHERTO KKPORTED SUGAR 

 PESTS IN OTHER COUNTRIES. 



2. Seeing then that our leaf-hopper was an imported species, 

 in a Report to the Hawaiian Sugar Planters' Association, written 

 on Nov. 15th, 1902, I stated that it was of the utmost importance 

 for us to learn whether our leaf-hopper \\ere one of those al- 



