GRASSHOPPER OUTBREAK IN NEW MEXICO. 11 



tude. After Priononyx has completed a nest, a Megastizus will locate 

 it, reexcavate the burrow, and proceed to destroy the egg deposited 

 upon the nymph by the sphecid. This egg is apparently destroyed 

 by the Megastizus crushing it between her mandibles. The Megas- 

 tizus then deposits upon the nymph an egg of her own. 



Megastizus is not particular about refilling the burrow, nor does she 

 attempt to hide the location of it in any manner, as does the Prio- 

 nonyx. Oftentimes Megastizus will leave the nest when the burrow is 

 not more than half refilled with soil. Occasionally the Priononyx 

 will be driven from her nest by Megastizus while in the act of filling 

 up her burrow. Neither Priononyx nor her nest, however, were ever 

 noted to be disturbed by Megastizus until after the prey had been 

 placed in the burrow. 



Megastizus never attempted to sting a grasshopper during the 

 present observations, but preyed upon Priononyx entirely, in the role 

 of a secondary within the sphecid's nest. Being present in consid- 

 erable numbers, it most certainly affected the efficiency of Priononyx 

 to a great extent. 



ARTIFICIAL REMEDIES. 



The most effective artificial means of exterminating the grasshop- 

 pers of this species was found in the use of the poisoned bran mash. 

 This was made as follows : Thoroughly mix together in the dry state 

 25 pounds of wheat bran and 1 pound of Paris green. Into a sepa- 

 rate receptacle containing 2 quarts of a cheap molasses or sirup add 

 the juices and finely ground skin and pulp of three oranges or lemons. 

 Dilute the molasses mixture in 2 gallons of water and add to the 

 poisoned bran mixture. Thoroughly mix the two together, adding 

 enough more water, if necessary, to bring all to a stiff dough. This 

 amount of poisoned bait will treat from 5 to 10 acres. 



The bait should be sown broadcast early in the morning, before 

 sunrise, in strips 1 rod apart, over the area to be treated. The 

 most satisfactory method of distributing the bait is to sow it from 

 the rear end of a buggy. 



In using the poisoned bait as above, with lemons as the fruit em- 

 ployed, tremendous numbers of the grasshoppers were exterminated. 

 As many as 75 dead grasshoppers per square foot were frequently 

 found, several days after the application, over large areas. The 

 grasshoppers usually die from 6 to 80 hours after taking the poisoned 

 bait into the system. 



Coarse-flaked brans should be used in preference to the fine-flaked 

 varieties. Only those brands of Paris green which are guaranteed 

 to contain not less than 55 per cent of arsenic should be employed. 

 Arsenate of lead should not be used in any form. There have ex- 



