342 BRITISH ANTS. 



Bot. Gard. Kew 3 122 (1908) 4 : Trans. Leicester Lit-Phil. Soc. 12 231 (1908) 6 : 

 Bull. R. Bot. Gard. Kew 6 251 Pf. [l]-9 (1909) 6 . 



Habitat : West Indies. 



Several workers were taken in the propagating pits in 1904 

 (Godfrey] and again in 1905 (Stewart], Edinburgh Botanic Gardens 3 . 

 There is a winged female from the same source in the British 

 Museum Collection. 



I captured a few workers under flower-pots in the propagating 

 pits, Kew Gardens, December, 1907 4 5 , and a few have occurred 

 since. 



DOLICHODERINAE. 



Iridomyrmex humilis Mayr. 



Hypoclinea humilis Mayr Ann. Soc. Nat. Modena 3 164 (1868) 1 . Iri- 

 domyrmex humilis Dalla Torre Cat. Hym. 7 169 (1893) 2 ; Carpenter Econ. 

 Proc. R. Dublin Soc. 1 155 (1902) 3 ; Donisthorpe Trans. Leicester Lit-Phil. 

 Soc. 12 229 (1908) 4 ; Foster Journ. Econ. Ent. 1 289-293 (1908) 5 ; Wood- 

 worth Univ. Cal. Agri. Exp. Stn. Circ. 38 1-11 (1908) 6 ; Newell Journ. Econ. 

 Ent. 2 174-192 (1909) 7 ; Wheeler Ants 153-155 (1910) 8 ; Forel Int. Ent. 

 Cong. Bruxelles 1910 2 83 (191 1) 9 ; Emery Gen. Ins. 137 26 (1912)1. 



Habitat : Argentine ; Brazil. 



This species is known as the " Argentine Ant " ; it is rapidly be- 

 coming cosmopolitan, and when once introduced into a new locality 

 it may become a very serious pest. It displaces local species, and 

 seems to have entirely exterminated Pheidole megacephala in 

 Madeira 8 . It has been introduced into New Orleans 5 and Cali- 

 fornia 6 ; in the former locality it now extends over fully five 

 thousand square miles from New Orleans to the Gulf of Mexico. 



Newell has written an interesting account of the life history of 

 this species 7 . 



Carpenter records its occurrence in vast numbers in a house in 

 Windsor Park, Belfast, in 1900, where it had been observed for 

 eighteen months. The ants were present in the laundry, con- 

 servatory, and vinery, crossing the kitchen yard in great abundance. 

 The ants were only got rid of with the greatest difficulty ; the 

 floors were taken up and eight large nests were found at a depth 

 of three to four feet ; they were also present in the walls. Waterston 

 in 1912 sent me specimens of this ant to name, taken in the Botanic 

 Gardens in Edinburgh. 



Tapinoma melanocephalum F. 



Formica melanocephala Fabricius Ent. Syst. 2 353 (1793) 1 . Tapinoma 

 melanocephalus Billups Proc. Ent. Soc. Lond. 1887 XXVII 2 . Tapinoma 

 melanocephalum Dalla Torre Cat. Hym. 7 165 (1893) 3 ; Godfrey Notes R. 

 Bot. Gard. Edinburgh 17 102 (1907)* ; Forel Int. Ent. Cong. Bruxelles 1910 

 2 83 (1911) ; Emery Gen. Ins. 137 41 (1912). 



Habitat : Cosmopolitan species. 



Billups captured this ant in September, 1886, on a palm in the 

 palm house in Kew Gardens 2 ; Godfrey records finding a nest in 



