59-57. q6 D (7) 



Article XIX. — THE NORTH AMERICAN ANTS OF THE GENUS 



DOLICHODERUS. 



By William Morton Wheeler. 

 Plates XII and XIII. 



Four species of the mainly tropicopolitan genus Dolichoderus have 

 been recorded from America north of Mexico and the West Indies, 

 namely: D. maricE Forel, tascJtenbergi Mayr, plagiatus Mayr, and 

 pustulatus Mayr. When in 1886 the latter author published a com- 

 parative description of all of these forms, he called attention to their 

 close affinity with the single European and Siberian species, D. 

 quadripunctatus L., and to their still closer relationship with one 

 another.i Mayr even maintained that the four forms might be re- 

 garded as varieties of a single species, but owing to the absence of 

 annectent variations he preferred to let them stand as separate 

 species. They were based on worker specimens, though he briefly 

 described the females of inarics and pustulatus. 



That during the past twenty years our meagre knowledge of these 

 interesting ants has remained in statu quo, must be largely, if not 

 exclusively, due to their scarcity or extremely local distribution. 

 Having recently found two of the species, D. marice and a variety of 

 taschenbergi, rather common in the pine-barrens about Lakehurst, 

 New Jersey, I decided to study the peculiarly North American Doli- 

 choderi in my collection and to publish a revision of the species, 

 together with some notes on their hitherto unknown habits. As a 

 result of this study, I cannot say that I am prepared to merge all 

 four so-called species into one, but nevertheless I feel certain that 

 pustulatus is merely a subspecies of plagiatus. The only differences 

 I can detect between these two forms are in size, sculpture, and 

 coloration . Among my specimens there are individuals representing 

 a distinct variety or subspecies of each of the four Mayrian species, 

 and showing that these, like most of our North American ants, are 

 decidedly variable. I am able to add descriptions of the male of 

 maricB and of the male and female of the typical plagiatus. 



It is a singular fact that the Dolichoderi of America north of Mexico 

 and the West Indies are all confined to the humid eastern portion of 

 the continent At any rate none of the species is known to inhabit 



* Die Formiciden der Vereinigten Staaten von Nordamerika. Verhandl. k. k. zool. bot. 

 GeseU. Wien, XXXVI, 1886, p. 434- 



\_November, igoj.] [SoS] ^^ 



33^98 



