92 



ARROWROOT. 



THE A.RROWROOT WORM (Calpodes ethliuSj Cramer). 



Lepidopl era. 



The larva of this insect, which occurs throughout the 

 American tropics, feeds on arrowroot and canua. The eggs 

 are laid on the leaves of the food plant, and the larvae, as 

 soon as hatched, begin feeding, protecting themselves from 

 view in a fold of the leaf, which they make by drawing over 

 the margin of the leaf and tying it down with a piece of silk. 

 The caterpillars are greenish in colour, and very delicate in 

 appearance. The skin is so thin that it is possible to distin- 

 guish a good deal of the internal anatomy. The caterpillar 

 has a very peculiar appearance on account of the small neck 

 which is characteristic of the insects of this group. The 

 adult (Fig. 102) is brown in colour, with angular white spots 

 in the wings, the under surface being lighter than the upper. 



Fig-. 102 



Natural size 



Canna Moth. 

 {Original.) 



This insect belongs to a group of the Lepidoptera called 

 skippers, which is intermediate between the butterflies and 

 the moths. The most prominent characters of the group are 

 the clubbed antennae terminating in a fine hook in the adult, 

 and the broad head and small neck in the larva. 



Control. The eggs of the arrowroot worm are para- 

 sitized by a minute hymenopteron (probably Trichogramma 

 pretiosa), and it is likely that blackbirds, and the predaceous 

 wasps, such as the wild bee and others attack the larvae. 



