48 FROGHOPPER BLIGHT OF SUGAR-CANE. 



Moore in his Annual Report for 1918 (1919 p. 7-13) gave a fuller 

 account of the outbreak and came to similar conclusions. He con- 

 sidered that the abnormally wet weath<!r of the first six months of the 

 year was the cause of ihe serious infestation. The soil became water- 

 logged, grasses and weeds grew apace, and could not be kept within 

 b( unds, and as a result of this the canes had already sufifercl before the 

 froghoppers appeared. Mocre made further observations on the eggs. 

 which he recorded as abundant in the loc^se soil of worm castings, and 

 also pointed out the close relation between the abundance of the 

 insect, the severity of the damage, and the texture of the soil, the canes 

 on heavy clay soils being in every case more damaged than those on the 

 lirrhter soils. 



No serious attack seems to have occurred in 1919 but the conditions in 

 l-Jritish Guiana at present resemble very closely indeed those prevailing 

 in Trinidad about tlie year 1906 when the insect, after being of small 

 consequence for many years, suddenly demonstrated its power ; it is to 

 be hoped that British Guian i will not experience a series of attacks 

 "similar to those which have occurred in Trinidad since that year. 



COLOMBIA. 



In 1913 Vargas Vergara published, a shoit note on the damage done 

 by Tomas])is bogotensis {see I'laty I Fig. 10) in Colombi.i. He stated 

 that for many years the pastures in the Tocaima and Casai Viejas 

 region had suffered severely from the ravages of this insect, locally 

 known as "el mion'. Tocaima is about 30 miles W.S.^Y. of Bogota 

 a id is about 190 miles from the Tacific ; Casas Viejas I have been 

 unable to locate. 



Since that date several inquiries have been received by Mr. Urich as 

 to methods of control and the use of green" nmscaidine. so that 

 apparently the damage still continues. 



BAN\MA. 



No froghopper of the genus Tomaspis appears to be of serious con- 

 sequence in this country. In the collection of the U. S. National 

 i\Iuseum of Washington are three specimens of Tomaspis lepidior. 

 Fowler (Plate I Fig. 11) labelled "Panama, injuring gi-ass. Dr. A. 

 Precindo" and Urich (1913 C. p. 8) mentions that Mr. A. Busck found 

 the same species on cane where it was well known to the natives. 



Of n;iore importance from an economic point of view is a froghopper 

 of quite different habits and relationships, an undescribed species of 

 the genus Clastoptera which I found in Panama and Costa Rica damag- 

 ing the flowers of cacao {Theohroma cacao). 



The insect is scarcely one third the size of Tomaspis saccharina and 

 the nymphs live, several together, in masses of froth on the flower 

 stalks of the cacao. The flower is killed and drops off, and in heavily 

 infested trees as many as 75 per cent, of the flowers were destroyed in 

 this wa}-. It is only the fact that the cacao tree usually produces a 

 large excess of flowers that prevents the insect being a serious danger 

 in the localities where it occurs. 



The cacao froghopper was also of particular interest as the froth was 

 found to contain the larvae of a fly [DrosopJiila sp. ) not previously 

 known as a froghopper parasite, {see p. ). A fuller account of this 



insect is in preparation and will be published later. 



