96 



THE COCO-NUT 



CHAP. 



days. The larva is at first 3*5 mm. in length, and 

 grows to about 45 mm. This insect lives upon the 

 betel-nut palm also. It is preyed upon and held in 

 check by hymenopterous parasites, and Banks does 

 not believe that it is likely to become a dangerous 

 pest. 



He holds the same opinion regarding the moth 

 Thosea cinereomarginata, the larva of which is a slug- 

 caterpillar, easily recognized by haviug along each side 

 of the body a row of spinous tubercles. Like the 

 insect just described, this does moderate injury to coco- 

 nut leaves in Manila. 



TJwsea and Padraona, and with them Erionota 

 thrax, another of the skippers, are known in the 

 Federated Malay States. 



Another butterfly, whose larvae live upon the leaves 

 of the coco-nut in the Philippines, is Amathusia 

 phidippus. The same insect is found in British India, 

 where its food-plant is also the coco-nut. It is not a 

 common butterfly here, and is not known anywhere to 

 do very great damage. Jb. Coert, nevertheless, states 

 that in the Dutch East Indies the larvae sometimes 

 become numerous enough to defoliate trees (see Wilborn, 

 in Bull Kolon. Museum, Haarlem 41 (1909), 122). 



Very serious local damage is reported by Schultz, 

 the horticulturist of the Canal Zone, as done to the 

 coco-nuts of Panama by Brassolis istlimia. In May 

 1906 the majority of the coco-nut trees in the vicinity 

 of Ancon were defoliated by its caterpillar. Trees 

 which had been prolific for several years were left with 

 their bare petioles and midribs looking like skeletons. 

 Some trees recovered, under special care ; others were 

 cut down. In September the caterpillars again appeared 

 in smaller numbers. " All coco-nut trees were, there- 

 fore, sprayed with a strong solution of arsenate of lead, 

 a most tedious and troublesome, although very effective, 

 method of fighting these insects, in view of the height 

 of the trees, which were mostly from 30 to 35 feet." 

 Rain washed the poison off within a few weeks, but all 



