A^EGETxVBLE INSECTS. 281 



The larva of this si)ecies looks very similar to that of the preced- 

 ing species, hut the adult is dark hrown in color, witli transverse 

 white bauds across the wings. 



Control. — Methods of control are the same as for the preceding 

 species. 



OTHER BEET PESTS. 



Other insects attacking beets are: Xacoleia indicata (see Beans, 

 page 275) ; Systoia hasalis (see Carrots, page 284) ; Xylomeges 

 sunia (see Chard, page 287) ; leaf -hoppers (see General Feeders, 

 page 272). 



CABBAGE. 

 THE DIAMOND-BACK MOTH (Phifella macniUpcnnis) . 



This minute moth is undoubtedly the worst insect pest of cab- 

 bages in Porto Rico. The small green caterpillers or worms oecui- 

 in large numbers on the undersides of the leaves, riddling them with 

 holes. These holes do not extend completely through the leaves, so 

 that the leaves have a skeletonized appearance and when blown by 

 the wind they crackle like paper. 



This pest is at its worst during the summer months and unless 

 effective measures are used to control it, it is iini>ossible to raise good 

 cabbages. 



When full grown, the small caterpillars si)in loose silky cocoons 

 on the undersides of the leaves in which they pupate. The adult is 

 a very small grayish moth with patches of white along the borders 

 of the front wings. When the wings are folded, these white areas 

 form the diamond-shaped markings that give the moth its name. 



ControL — The leaves of tlie cabbage should be spraj'-ed on the 

 undersides witli arsenate of lead tliree pounds to fifty gallons of 

 water. A sticker should be added to tliis spra.s' as the leaves of the 

 cabbage are covered with a waxy secretion. For fornnila see page 267. 

 If the worms iuive become abundant before being discovered, the 

 cabbages should be sprayed with a kerosene cinnlsion s|n'ay diluted 

 on<> to fifteen. For directions t'ci' making the emulsion see page 268. 



THE SOl'TllKRN CABBAGE Br-TTERE!-V (/'(DlHd in(J)nisl (') . 



This butterfly is usually to be seen Hying al)out {)atches of cab- 

 bages and other cruciferous plants, it deposits clusters of bright 

 yellow eggs on the u]>per surface of the leaves, and these soon hatch 

 into hairy greenish-yellow caterpillars. 



