SECTION V. — TRINIDAD FROGIIOPPER. G'.i 



Moore (1919 p. 12) is strongly' of the opinion that in British Guituia, 

 with their froghopper, the dry season is survived by a few individuals 

 which continue breeding in the more favourable moist locaHties. It, 

 nmst however be remembered that conditions in the cane fields in 

 liritish Guiana even at their driest season are never comparable with 

 those of Trinidad. The dry seasons are shorter and less severe and the 

 fields are low-lying and capable of being irrigated, and as a result it is 

 seldom that there are not in every field moist spots in the drains where 

 lireeding can continue. 



Kershaw (1913 D. p. 3) dissected a number of eggs during the dry 

 season and found them all in the same stage of development ; the 

 primitive band had formed and invaginated, and the embryo had 

 segmented but no appendages had been formed. 



Although there is no doubt that the drj' season in Trinidad is 

 generally passed over in the egg stage, there are some exceptions, to one 

 of which attention must be drawn here. 



Throughout the whole of the drj? season (January to April) of 1918, 

 following the severe blight of 1917, adult froghoppers were found in 

 considerable numbers in a field of young plant canes in the Naparimas. 

 The numbers were not large, varying from two adults to every throe 

 plants in March to one adult to every seven plants at the end of April. 

 During the months of March and April there was only I'l inches of rain 

 on this estate. At the beginning of April adults were noticed pairing. 



This continuation of normal activities of the adult through )ut 

 extremely dry weather is very unusual, and is recorded here chieHy in 

 the hope of an explanation being forthcoming later. 



OTHER FROGHOPPERS IN TRINIDAD. 



There are four species of the genus Tomaspis known in Trinidad : 

 T. rtibra, T. pubescens, T. guyp^ji, and one unidentified. In addition 

 two other genera, Clastoj^tera and Cephisns are also represented. 



Tomaspis rubra (Plate 1, Fig. 19) is a species considerably larger 

 than T. saccharina, dark brown with two transverse yellow bands. T'le 

 same insect is recorded from the mainland and Grenada, but all the 

 specimens seen from the mainland (Venezuela, Britisii Guiana, Surinam) 

 have the hind band as wide as the front one, whereas in the Trinidad 

 and Grenada specimens the hind band is definitely narrower. 



The insect feeds in the nymph stage on the roots of the Christmas-bush 

 (Eupxitorwm odoraturn) and according to Urich (1913 C. p. 29) the eggs 

 are laid in the rootlets of the food plant. The insect is generally 

 common in the cacao and bushy districts of the island, and is of no 

 economic importance except in so far as it is sometimes mistaken for 

 the sugar-cane froghopper. 



Tomaspis pubescens Fabr. (Plate 1, Fig. 15) is about the same size 

 as T. saccharina but greenish black in colour. The female is distinctly 

 more pubescent than the male. Trinidad specimens are distinctly 

 smaller than those from British Guiana and Surinam. 



In habits it closely resembles the sugar-cane species. It feeds on 

 various species of grass, but prefers very moist localities by the banks of 

 streams in the wooded parts of the island. The froth formed by the 

 nymph is nuich firmer and more glutinous than that of T. saccharina. 



