A general historical account of the distribution and economic status of the ants of these islands, particularly the relation of the Argentine ant, Iridomyrmex humilis Mayr, to local agriculture. The 56 forms known to the islands are listed, with notes on synonymy and distribution. New forms are: Monomorium hesperium v. lanzarotense (p. 107), M. salomonis ssp. subopacum v. intermedium (p. 108), Leptothorax risi ssp. armouri (p. Ill), and Tetramorium caespitum ssp. semilaeve v. palmense (p. 113).