535 



The eggs are deposited in a cylinder- shaped cluster round the stems 

 of weeds or grass during September, October and November, the 

 caterpillars hatching usually in May or June. The newly-hatched 

 caterpillars feed in groups and when resting, or in cold wet weather, 

 form conspicuous masses. They pupate in August or September, this 

 stage lasting a month or six weeks. 



The caterpillars are attacked by Dipterous parasites, including 

 Tachina niella, and by Hymenoptera, including Pimjda conquisitor. 

 Large numbers of the pupae are destroyed by skunks. Badgers, 

 coyotes, mice and robins, as well as several ground beetles, ants and 

 robber-flies also destroy this pest. The eggs are eaten by two different 

 kinds of camel-crickets. Insect enemies of these groups, including the 

 ground beetle, Calosoma sycophanta, have also been introduced from 

 Massachusetts, Indiana, Kansas, Missouri and California. A wilt 

 disease in some seasons destroys large quantities of caterpillars, but as 

 this only occurs at rare intervals, it is not a sufficient check upon them. 



Mechanical control measures which are suggested include : — 

 Burning the pasture, rolling and brush- dragging the ground, and the 

 use of sheep and turkeys. These measures are not practicable however 

 on land of little value. Cereal crops are best protected by powdered 

 arsenate of lead. When so treated, these must not be used for grazing 

 until after heavy rains have fallen, and 30 days at least should elapse 

 between spraying and their use as fodder. 



Marlatt (C. L.). House Ants : Kinds and Methods of Control. — 



U.S. Dept. Agric, Washington, D.C., Farmers' Bull. no. 740, 

 8th July 1916, 12 pp., 5 figs. [Keceived 19th October 1916.] 



Nearly all the ants in North America that frequent houses are of 

 tropical origin, and they are mostly Old World species. Those 

 introduced from the Old World or South America have entered the 

 country chiefly in ships' cargoes. In their native country they are 

 probably outdoor species, but in temperate regions they are obliged 

 to dwell in houses, hot-houses or mills in order to obtain adequate 

 warmth. 



The North American house ants fall into four groups, according to 

 their country of origin. Tropical Old World ants are represented by 

 the little red ant or Pharaoh's ant, Monomarium pharaonis, L. 

 Originally a soil ant, it continues this mode of life in the tropics, and is 

 only found in heated houses in temperate zones. M. salomonis, L., 

 M. destructor, Jerd., and M. floricola, Jerd., have been reported 

 occasionally in dwellings, particularly in the southern United States. 

 Solenopsis geminata, F,, subsp. rw/a, Jerd., and Pheidole megacepliala, F., 

 are now fairly well estabhshed and are potential house pests. The 

 latter, formerly an important house ant in Madeira, propagates rapidly 

 in subtropical countries and will exterminate indigenous species. 

 Prenolepis longicornis has acquired a footing in Florida, and has been 

 reported as infesting large buildings in New York and Boston. It is 

 believed to have originally come from India. The most important of 

 imported tropical New World ants is Iridomyrmex humilis, Mayr, 

 (Argentine ant), which is a serious pest in the citrus orchards of 

 southern California and is the only species which causes large financial 

 loss, the others being merely annoying. Four other South American 



