193 



parasitef which deposits its eggs within the body of the 

 larva or pupa, where the parasite grubs feed and develop 

 at the expense of the cotton worm. 



The larger wasps, the cow bee, wild bee and Jack 

 Spaniard are very important predaceous enemies of the 

 cotton worm, in the West Indies. These insects build 

 nests of paper ; in these they deposit their eggs and the 



Fig. 183. Cow bee. 

 Enlarged. (From U.S. Dept. Agric.) 



young are hatched and reared to maturity in them. The 

 adult insects, of which there are generally several 

 attached to each nest, go in search of food, which they 

 bring to the helpless grubs. This food consists largely of 

 caterpillars, and when the cotton worm is present in large 

 numbers they are very much sought after by these insects. 



The number of caterpillars caught during a season by 

 wasps is very great, and it is considered in St. Vincent to 

 be due to these insects that the cotton worm has not devel- 

 oped sufficiently to become a pest in that island. 



It is likely also that many other leaf-eating caterpillars 

 are controlled to a very large extent by these insects. 



Cotton worms are also eaten by toads and birds ; of the 

 latter, perhaps the most useful is the blackbird. 



The ground beetle is known to occur in St. Vincent and 

 Barbuda, where it has been observed feeding on cotton 

 caterpillars. It may occur in other islands, and probably 

 would be a very useful check on these insects if it were 

 present in sufficient numbers, since both the beetle and its 

 grub are predaceous in habit. 



