169 



A Geometrid and a Hesperid are unimportant pests ; an Aphid 

 pest is preyed upon by SjTphid flies, the pupae of which are themselves 

 parasitised by a Hymenopteron. A Braconid parasite has also been 

 reared from this Aphid. 



The arrowroot worm, Calpodes ethliiis, Or., was controlled b}' 

 parasites, which included three species of Tachinid flies. 



A table is given showing the parasites and leaf-miners that have 

 been reared during the year. 



A small moth has been found parasitising the predaceous and 

 beneficial wasp, Polistes annularis. 



BoDKm (G. E.). Report of the Economic Biologist. — Rept. Dept. Sci. 

 & Agric. B. Guiana, for the Nine Months ended 31st December 

 1915. Georgetown, 12th July 1916, 10 pp. [Received 27th February 

 1917.] 



No substantial change in the status of insect pests connected with 

 sugar-cane is recorded. 



An ant, Attn {Acromyrmex) octospina, Reich., was observed to 

 remove the layer of tissue immediately overlying the cambium of 

 recently tapped rubber trees, causing considerable damage. It 

 forms nests in hollow, decaying logs, which are easily destroyed without 

 the aid of chemicals. It has only been observed in one locality. 



Two formidable pests of coconuts were active in difTerent parts of 

 the Colony during this period. Brassolis sophorae, L., again made 

 its appearance on the east coast, defoliating large areas of palms, 

 and a nest was found at Potaro, though it appears to be now almost 

 extinct in Georgetown. It is preyed upon by the kiskadee {PiianguH 

 sulphuratus). The district was proclaimed under the Plant Diseases 

 and Pests (Prevention) Ordnance, with some good effect, but the 

 pest showed a distinct tendency to spread along the coast. On the 

 Upper Courantyne Coast a large Acridiid, Tropidacris latreiUei, 

 Perty, made its appearance in great numbers and rapidly defoliated 

 the coconut palms in the district ; consequently a large area was 

 there proclaimed under the Ordinance. The Coccid, Aspidiotvs 

 destructor, Sign., continues to be destructive in some areas. Two 

 additional minor pests are the Lepidoptera, Perichares corydon, ¥., 

 and Opsiphanes cassiae, Feld. 



Citrus plants were attacked by the larva of an undetermined species 

 of Papilio and by Heliothrips haemorrhoidalis, Bch. No serious 

 pests were observed. The weevil, Heilipus ocellatus, F., was observed 

 attacking the bark of young pines. The larva of a fruit fly has been 

 found in the fruit of imported orange trees. The guava fruit fly, 

 Anastrepha striata, Schin., is the only fruit fly of importance at present 

 known to occur in the Colony. 



The attacks on rice by the two leaf- eating caterpillars, Laphygrna 

 frugiperda, S. & A., and Pelamia {Remigia) repanda, F., have only 

 been slight, but the ant, Solenopsis pylades, Forel, has been observed 

 to hollow out the stems of fully grown rice plants. In one instance 

 it was noticed to attack and destroy a larva of Diatraea which was 

 occupying the stem. 



The pests of vegetables, garden-plants and fruit have been 

 given some attention. Cucumbers and pumpkins were attacked by 



