4 INSECTS IN SHIPMENTS OF SUGAR CANE. 



small, winged creatures, and leap readily when disturbed. The 

 froghoppers breed in cane fields which are damp and grassy. A 

 good method of control is to keep the cane fields free from rank weeds 

 and tall grass. A species of froghopper was found last summer on 

 cane and grass near New Orleans by Mr. Gilbert E. Bodkin, Govern- 

 ment economic biologist of British Guiana, who examined some cane 

 fields in company with the writer. Specimens of these insects were 

 sent to Dr. F. W. Urich, entomologist of Trinidad, who states that 

 the species is not the same as the one which occurs in his vicinity. 

 Dr. Urich writes as follows: 



1 would strongly advise you to make an effort to eradicate this insect from the grass 

 surrounding cane fields, for if they get established in sugar canes there is no knowing 

 what may happen. Our froghopper trouble originated in gra.ss. 



THE LEAFHOPPERS. 



Apparently we have several loafhoppers in this country, but they 

 do not seem to be injurious. In Hawaii, however, there is a de- 

 structive leafhopper {Perkinsiella saccharicida Kirkaldy) which was 

 introduced from Queensland, Australia. The manner of introduction 

 and dispersion is described in an interesting way by Mr. D. L. Van 

 Dine * in the following words : 



The main factor in the distribution of the pest is the habit of the female of depositing 

 her eggs beneath the epidermis of the internodes of the cane stock. It seems probable 

 that the pest was introduced into the islands and to a great extent distributed over 

 the cane districts in seed cane. In local distribution other factors present themselves. 

 The leafhopper is an insect readily attracted by light at night, as its presence about 

 lamps in the factories and homes on the plantations testifies. Passengers and steam- 

 ship officers of the interisland steamers have frequently stated to the writer on inquiry 

 that in many instances, especially at night, great numbers of the insects have come 

 aboard in certain ports or when offshore from certain plantation districts. These 

 adults have undoubtedly traveled in this manner from one locality to another, so 

 that an uninfested district might easily have become infested while stopping at or 

 passing by an infested locality. Railway trains have been equally active in the 

 spread of the insect on land. 



Another mode of distribution during the general outbreak of 1903, under conditions 

 of heavy infestation, was the migration of the pest from one locality to another during 

 the daytime. These migrations were observed by many of the planters. The man- 

 ager of one plantation in the Hamakua di-strict of the island of Hawaii stated to the 

 writer that in the early evening of April 26, 1903, the atmosphere was "thick with 

 hoppers" for a distance of 2 miles and that the "hoppers" were traveling with the 

 prevailing wind, about southwest. Similar migrations, described by the observers 

 as "clouds," were mentioned by other managers. 



The characteristic injury of this leafhooper is also noted by Mr. 



Van Dine : - 



The presence of the pest on the plantations was noticed first by the appearance of 

 a sooty black covering on the lower leaves of the cane plant. This black covering 

 became known as smut. It is a fungous growth and finds a medium for development 

 in the transparent, sticky fluid secreted by the leafhoppers during their feeding on 

 the plant. This secretion is commonly known as honeydew. 



' The Sugar-Cane Insects of Hawaii. By D. L. Van Dine. Bui. 93, Bureau of Entomology, U. S. 

 Department of Agriculture. Washington, 1911. 



2 Previous reference. 



