386 



of pupating either in the disused nest or elsewhere in the crown of 

 the tree, frequently descend the trunk of the palm and pupate in the 

 empty husks and other debris lying about the base. The clearing 

 up of all rubbish and empty husks on infested areas has consequently 

 been made compulsory. This pest is apt to lie dormant for a time 

 and then make a severe attack, palms being rapidly stripped of their 

 fohage,.and eventually the caterpillars, being unable to obtain food, 

 scatter and pupate in the most convenient spots, thus rendering 

 their destruction a difficult matter. These sudden infestations are 

 undoubtedly regulated by the abundance of natural enemies, princi- 

 pally Hymenopterous parasites. The larvae of the Limacodid, 

 Sihine fusca, Stoll, are increasing in numbers and on several occasions 

 have been found to cause an infestation ascribed to B. sopJwrae. 

 The large locust, Tropidacris latreillei, Perty, formerly a serious pest, 

 has now almost completely disappeared. The larvae of the moth, 

 Castnia daedalus, have continued their depredations in certain areas. 

 In several cases the beetle, Strategus aloeiis, L., was found to have 

 descended to a considerable depth and destroyed the entire heart 

 of a young palm. 



Neither citrus plants nor rice are seriously infested by any insect ; 

 on the former scale-insects are the worst pest ; on the latter Lajjhygma 

 frugiperda, S. & A., still occurs, though not abundantly. 



Cacao trees have been found infested wdth the following species 

 of ants, their presence being frequently indicative of scale-insect 

 infestation : Daceton armigerum, Ltr., Cryptocerus atratus, L., Tetra- 

 morium guineense, F., Neoponera villosa inversa, Sm., Azteca instabilis^ 

 Sm., and A. velox, Forel. 



Investigations were carried out on the sugar-cane froghopper pest, 

 Tomaspisflavilatera. Both this species and its parasites were studied, 

 with the object of the possible introduction of the latter into the cane- 

 fields of Trinidad. Froghoppers are not likely to become a serious pest 

 in British Guiana. The follo^\dng species have been identified : 

 Tomaspis flavilatera, Urich, the nymphs of which feed on sugar-cane ; 

 T. pubescens, F., the nymphs feeding on grasses in the vicinity of 

 cane-fields ; T. rubra, Germ., abundant in the interior ; and Ischnorhma 

 sanguinea, F., a rare species from the interior. 



Among destructive ants are Atta (Acromyrmex) octospino, Reich., 

 w^hich destroys the cambium layer of recently tapped rubber trees 

 {Hevea brasiliensis) ; Monotnoriimi jioricola, Jerd., found infesting 

 coconut palms and also in houses i*n all kinds of food, ^particularly 

 oils, and devouring dead insects. Tapirwrna melanocephalum, F., is 

 perhaps the commonest species of ant in the Colony ; it is found in 

 every dwelling-house and building, attacking all kinds of food and 

 also dead insects. Camponotus [Myrmothrix) abdotninalis stercorarius. 

 For., is common in cane-fields. Azteca trigona subdentata, For,, is- 

 usually found accompanying Coccids. Solenopsis pylades, For., is 

 the common red stinging ant of the coast-lands. It fosters Pseudo- 

 coccus saccJiari, Ckll. (sugar-cane mealy bug), P. citri, Risso, and 

 Saissetia nigra, Nietn. It is occasionally destructive to rice by 

 burrowing in the stem. 



Attention has been given to the dragonflies of the coast-lands, 

 some of which are of considerable economic importance, as they are 

 predaceous on certain agricultural pests. A list of 22 species occurring. 



