The Planters' Insect Friends. 35 



A caterpillar attacked by a Zelemorpha becomes quiescent, fixes 

 itself to the blade, dies, and then turns dark brown. The parasite 

 pupates within the caterpillar, and at the time of emergence gnaws a 

 hole in the back of the ninth and tenth segment. 



The caterpillars of certain Pyralid moths, species of Syngamia, are 

 badly parasitized by a Tachinid fly. There is also a brisk demand for 

 them by a wasp, a mud-dauber named Odynerus clavilinatus by 

 Cameron, which requires them to place in its cells to serve as food for 

 its larva?. It is most interesting to watch this wasp deliberately search- 

 ing the cane-blades for the caterpillars. Its actions show it to be as 

 much aware as the human entomologist that attention need be directed 

 only to folded blades. 



If we be in a thoughtful mood the spectacle reminds us that 

 hymenoptera used to sally forth on entomological expeditions at a period 

 in the earth's history antedating the appearance of man, and we cannot 

 but feel humbled by the fact that We are to a great extent mere copyists 

 of what — wasps ! Here we are in a field on the look out for folded 

 cane-blades to see if the folds contain caterpillars, and there along with 

 U9 is an Odynerus doing exactly the same thing, which it knew of before 

 we did, and getting through its hunting more expeditiously and, perhaps, 

 more successfully too, than we are getting through ours. 



The eggs of a leaf-hopper, one of the Fulgoridee, a sucking insect of 

 the plant-bug group, may often be seen in canefields. They are 

 deposited in the blade itself, just beneath the upper surface, in clusters of 

 about a dozen. They are laid side by side in a row. On a casual 

 glance they may be mistaken for eggs of the small moth-borer as the 

 spot in which they are laid turns yellow white and thus causes a resem- 

 blance to the egg-cluster of the moth-borer. They are parasitized by an 

 elongate black hymenopteron, which probably is mainly responsible for 

 keeping the leaf-hopper low down in the category of minor pests. 



A scale-iusect, apparently a Pulvinaria, is now and then observed on 

 cane-blades, its presence being always accompanied by busy throngs of 

 black ants. It never, however, becomes rampant, one reason being the 

 existence of a Chalcid which parasitizes it sometimes to the extent of 

 over 907. 



/o 



Various grasshoppers damage the can. -blades. Two of their insect 

 enemies are the Sphegid wasps, Spltcx ichneumoneus and Chlorion (Pro- 

 terosphex) neotropicus, which require them as food for their larvae. The 

 wasps, which first paralyze the grasshoppers by stinging, may now and 

 then be seen with burdens all but too heavy for them to carry. 



Coming to the insects which attack the cane stem, the first whose 

 enemies I shall deal with is the mealy-bug, which is a Coccid or scale- 

 insect, and one which is sometimes abundant enough to be a serious pest. 

 It has quite a number of insect enemies, being parasitized by certain 



