43 



PROGHOPPERS IN OTHER COUNTRIES, AND 

 LEGISLATION AGAINST FURTHER SPREAD. 



In summarising the proofs, of the responsibility of the froghop;)er 

 for the condition in sugar-cane known as "blight "it is mentioned (p. 123) 

 that similar damage is known in other countries in association with the 

 same or other species of froghoppers. 



In Central America records of damage are frequent and in nearly 

 every case the injury is to a grass or cane crop and is caused by a 

 froghopper of the genus Tomaspis, often closely related to the Trinidad 

 T. taccharina. The only case known outside Trinidad in which the 

 Trinidad insect itself has been found causing damage is in Grenada. 



A summary is given below of the froghoppers of Central America 

 recorded as causing damage, or in other ways important in the present 

 investigation. 



THE WEST INDIES. 



TOBAGO. 



Although only 22 miles from Trinidad in a direct line Tobago has its 

 own peculiar species of froghojaper. Tomaspis carmodiji, Kershaw 

 (Plate I Figs. 7 & 8) and the Trinidad T. saccharina has not yet been found 

 on the Island. The two are however closely related and difficult to 

 distinguish, but differ in several small points, chief of which are the 

 structure of the genitalia {see Kershaw 1913 D and F), the ground colour 

 of the wings, and the range of variation in the markings. 



T. carmodyi is darker than T. sxccharina, less variable and does not 

 have the light form with yellow at the base of tlie wings as in the 

 variety distanti of T. saccharina. 



On the other hand the two cross bands may be nuich reduced and 

 the whole insect almost unifoi-mally dark brown (Plate I Fig. 8), 

 a variation not found in the Trinida't species. 



All records of T. saccharina from Tobago up to the present have 

 been mistaken identifications. 



Although widely distributed in Tobago T. carmodyi has never been 

 recorded as damaging grass ur sugar-cane, and in this connection it might 

 be pointed out that the little cane now grown in this island is mostly in 

 mixed cultivation with other crops, particularly ground vegetables. 



The rainfall is as a rule more evenly distributed during the year 

 than in Ti'inidad, although the wet and dry .seasons are still distinct. 



I visited Tobago from the 9th to the 22nd Noveujber, 1916 and found 

 the vermilion parasite [Oligosita giraulti) present, and in September 

 1917, P. L. Guppy found a maggot of the Syrphid Fly (Salpingog aster 

 igra.) {See p. 67.) 



The green muscardine fungus was not seen and has not yet been 

 recorded. 



