SECTION IV. — LKGISI.ATION IM OTlIIiR COUNTKIKS. 47 



the outbreak liiid occurred. A short report has iih-eady been pubUshcd 

 (Wilh'ams 1917). Very little damage was apparent at the time of my 

 visit and the most interesting feature was that the froghoppor differed 

 considerably in habits from T. saccharina. The nymph stages in the 

 fi-oth were not on the roots but were all on the stalk of the cane above 

 ground, usually under the leaf sheaths of the cane from three to four 

 feet up from the ground. In this connection it is interesting to note 

 that in Tomaspis qupi^iji, the only froghopper that we have in Trinidad 

 that is structurally related to T. tristis, the few nymphs so far dis- 

 covered have been above ground on the stalks of grass. {See p. 64.) 



Tomaspis tristis is also known to occur in ]5ritish Guiana but so 

 far has not been reported from sugar-cane, nor has T. gup'pyi in 

 Trinidad yet left its native host plants. 



BRITISH GUIANA. 



A froghopper, Tomaspis flavilater a, Urich (Plate I Fig. 5) had been 

 known on sugar cane in British Guiana since about 1909. From that 

 date to 1916 small areas of some of the estates on the East Coast of 

 Demerara were frequently heavily infested, but no serious damage seems 

 to have occurred and the insect, ranked as a very minor pest of cane. 

 Short notes had appeared by Bodkin and Moore (see bibliography) but 

 it \\as not considered of sufficient injportance to warrant any special 

 investigation. 



In 1916 I visited the country in a search for parasites and sum- 

 marised the work up to that year and the results of my own investiga- 

 tions in a subsequent report (Williams 1918 B). 



The insect resembles very closely in habits the Trinidad sugar-cane 

 froghopper and both eggs and nymphs were found in similar situations. 

 A curious difference in the habits of the adults was however that in 

 British Gjuiana these spend the greater part of the day sitting on the short 

 succulent grass which grows by the moist drains through the cane fields, 

 and do not hide themselves in the axils of the leaves of the growing cane 

 to anything like the same extent as the Trinidad insect does. Advantage 

 was taken of this habit to reduce their numbers by catcthing the adults 

 during the day with strong cloth nets which were swept along the drains 

 by small boys. In this way several thousand could be caught in a day 

 by one boy at a cost nmch below that of the previous method of hand 

 collecting the nymphs. During September 1916 one estate caught 

 588,540 adults in this way at a cost of two cents (Id.) per hundred. 

 Forty-six per cent, of the individuals captured by this method were 

 found to be females. 



In 1917 H. W. B. Moore (1918 p. 12) continued his investigations and 

 made the important observation that the eggs were laid in the ground 

 as well as in the dead trash. " In one case a piece of earth about ^ of 

 an inch long, I in width and | in. thick had stuck in it over 60 eggs." 



The insect remained of very little consequence until May 1918 when 

 it suddenly appeared in enormous numbers in three widely separated 

 districts. 



G. E. Bodkin (1918 A.) reported the great increase of the insect and 

 warned planters to keep a strict watch for its appearance, and in a later 

 report (1918 B.) he stated that the insect " has demonstrated that it is 

 perfectly capable of doing immense damage." He was of the opinion 

 that the"^ sudden increase was due to abnormal climatic conditions, chiefly 

 heavy downpours of rain which caused the soil to become waterlogged 

 and the canes to become backward and stunted. The froghopper then 

 finished up the already weakened plant. 



