114 



bean leaf-roller {Eudamua proteun, L.) attacks several 

 varieties of beans. The caterpillar of this insect folds over 

 an edge of leaf to form a hiding place Tor itself. It is dis- 

 tinguished by its large head and a very small neck, and the 

 yellowish and green colour of its body (Fig. 131.) 



The bean leaf-roller never becomes very numerous, on 

 account of the extent to which it is parasitized by a small 

 hymenopterous iusect, Uror/aster leucostic/ma, Ashm. The 

 eggs of this insect are laid in the body of the caterpillar, 

 where they hatch and produce young grubs which feed on 

 the tissues of the caterpillar. When fully grown these 

 parasitic grubs penetrate the skin of the caterpillar and 

 form a mass of white, silky cocoons. Sometimes, these 

 grubs are so numerous that the mass of their cocoons 

 completely hides the caterpillar from view. This insect 

 furnishes an execellent example of parasitism, and it 

 would be well worth the while of any planter or 

 other reader of this pamphlet to collect a few of these 

 caterpillars and feed them in a glass covered with muslin 

 of order to have the opportunity of observing this example 

 in nature's method of preserving a balance among the 

 various forms of life. 



MISCELLANEOUS PLANTS AND PESTS. 



In addition to the plants Avhich are grown in the 

 West Indies as field crops, there are many others which 

 are cultivated in the kitchen garden, and in pots and 

 beds as ornamental and flowering plants. These are sub- 

 ject to insect attack, perhaps to even a greater degree 

 than field crops grown under estate conditions ; and any- 

 one who has attempted gardening must have been amazed 

 at the number of pests to be combated, if he has taken 

 notice of them. Most persons however merely attribute 

 the death or unhealthy appearance of plants to blight, 

 or worms, and never attempt any further classification of 

 the organisms operating to bring about the undesired 

 results. 



Plant lice, leaf hoppers, white fly, scale insects and 

 mealy-bugs occur on a great variety of food plants. They 

 are all insects with sucking mouth parts and would best 

 be controlled by contact poisons. Thrips and red spider 

 also are of frequent occurrence ; while leaf-eating cater- 

 pillars, grubs in the soil, borers in stems and roots, mole 

 crickets, cut worms, leaf-cutting bees, ants and nematodes 



