SECTION Vr. — NATURAL ENEMIES OF THE FROGHOPPEll. 91 



On one occasion the nesfc of a tick-bird was found with a rat in it 

 and the eggs broken. This nest was about seven feet from the ground. 



On another occasion a rat fled from the nest of a giouti on our 

 approach and on examination this nest was found to be damaged and 

 the eggs broken. 



Birds. 



In addition to the good that insectivorous birds do by eating the 

 adult and nymph froghoppers, it must be recognised that by destroying 

 the enemies of froghoppers they may to a certain extent cancel out their 

 previous value. Thus the tick-bird {Crotophaga ani) has been found to 

 eat spiders, grasshoppers (including Xifliidium) and preying mantids. 



The boat-tail {Quisqualus luguhris) eats lizards which would in turn 

 eat the froghoppers. The grey-headed keskadee has been observed 

 eating dragonflies, and the common keskadee has several times 

 been reported killing lizards. In fact, with regard to the latter bird, 

 Mr. Urich has put down the comparative abundance of tree lizards in 

 Grenada to the absence of our common keskadee. 



Lizards. 

 Even the lizards are not above reproach in the matter of their food. 

 On more than one occasion they have been seen to eat jumping spiders, 

 and dragonflies have been found in the stomach of a large species. A 

 more accurate investigation of the food of lizards is needed. 



Snakes. 

 Urich (1913 C. p. 24) reports that the snake Scytale coronatum eats 

 lizards, but that it is not very common on the sugar estates and he 

 tliinks that it is disappearing. 



Grasshoppers. (Xiphidmni.) 

 In captivity young XipJiidium have been found to eat miscellaneous 

 small Hymenoptera including the vermilion parasite. In the field their 

 diet is probably somewhat similar. 



Ants. 

 Ants, like all general predators, do not distinguish between insects 

 that are, to the agriculturist, useful or injurious. They have been 

 observed killing jumping spiders {AttidcB) and young XipJiidium. 



FossoRiAL Wasps. {Spliegidce.) 



Sphex ichneu7nonicus makes burrows in the soil in various parts of 

 Trinidad and British Guiana, particularly where the soil is light and 

 sandy, and stores them with the adults and nymphs of the grasshopper 

 Xiphiditim. Other wasps make mud nests and store them with spiders. 



They are in turn preyed on by other parasitic wasps and I have seen 

 hunting ants removing the grasshoppers from the burrow of the Sphex. 



Spiders. 

 These have also to be sometimes included among the hyper-parasites. 

 They have been said to be responsible for the failure of Urich's "Mexican 

 Bug" to establish itself here, and Guppy fomid that in captivity they 

 destroyed his Syrphid flies to such an extent that breeding these on a 

 large scale was impossible. 



Oligochaete Worm. 

 Under "The Syrphid Fly" p. 69 will be found particulars of a worm 

 believed to be parasitic in the pupa of this fly. It was found in Tobago 

 by P. L. Guppy. 



GiBELLULA Fungus. 

 This is an entomogenous fungus which destroys spiders. On several 

 occasions I have found it on jumping spiders in the cane fields. The 

 spider dies attached to the leaf and is covered with a mass of fungus 

 hyphse which are raised into vertical projections bearing spores. 



