THE ARGENTINE ANT IN RELATION TO CITRUS GROVES. J.3 



It is especially fond of sputum and the mucous secretion from the 

 bronchial and nasal passages, particularly if voided by persons 

 afflicted with a cold. The habit of the ant in getting into the mouth, 

 ears, and nose of infants, whenever opportunity offers, is probably 

 due to its fondness for mucus. Activities such as these, which are 

 habitual with the ants to the full extent that opportunity offers, 

 under certain circumstances obviously may be very important in re- 

 lation to sanitation. 



Living Insects as Ant Food. 



The flesh food most esteemed by the ants seems to be made up of 

 the insects which they capture alive. It is not solely for nectar that 

 they visit the flowers of citrus and other plants, but also for the 

 thrips, gnats, and other insects which they are able to capture there. 

 A certain proportion of the ants foraging in the trees almost invari- 

 ably are found to be carrying insects. The number so engaged will 

 depend upon the availability of these insects. In a large number of 

 observations on this habit, in all seasons, it was found that from as 

 low as 0.49 per cent to as high as 45.8 per cent of the ants foraging 

 in orange trees carried insects. Usually, however, less than 1 per 

 cent will be engaged in capturing insects, and when the proportion 

 is larger than 5 per cent it is because a special opportunity is offered. 

 For example, on fig trees in Louisiana there is usually a period of 

 emergence of psocids in the spring when other ant food is scarce, and 

 the ants hang around the psocid groups and capture the insects as 

 they emerge. Again, during the blossoming period of the small- 

 leaved privet the ants are able to capture numerous thrips from the 

 blossoms. The blossoms are narrowly campanulate, and the ants, un- 

 able to pass between the stamens, await and capture the thrips as they 

 attempt to leave. Large numbers of foraging ants are found carry- 

 ing white flies at each emergence period of the flies, on both orange 

 trees and privets. All these insects, of course, may be captured from 

 the same trees at the same time. For example, on one occasion, when 

 all the ants carrying insects on a privet tree in one and one-third 

 hours' time were captured and their prey examined, it was found 

 that 32.7 per cent of the prey were thrips (Frankliniella sp.), 46.5 

 per cent nectar-feeding gnats, 13.8 per cent white flies, and 5 per 

 cent psocids. Often, however, they are engaged almost exclusively 

 in the capture of one particular species. 



Large numbers of insects are captured on the ground, on weeds 

 and ornamental trees, and in manure piles in the orange orchards of 

 which no special account is taken because their capture has no bear- 

 ing on the relation of the ants to orange trees. The ants also capture 

 living and dead mealybugs, immature soft brown and black scales, 



