17^ Psyche [December 



ADDITIONS TO OUR KNOWLEDGE OF THE ANTS OF 

 THE GENUS MYRMECOCYSTUS WESMAEL.i 



By William Morton Wheeler. 



Since my paper on the honey ants was pubhshed in 1908 ^ our 

 knowledge of the distribution of these insects has been increased 

 and two new species have been brought to Hght. Mr. Percy 

 Leonard of the Raja Yoga Academy at Point Loma, Cahfornia, 

 has discovered a new subspecies of M. meUiger and has pubhshed 

 an interesting accoimt of its habits and of those of M. mexicanus 

 mojave.^ During the winter of 1910 I made a second journey to 

 Arizona and Cahfornia and was able to observe the latter and sev- 

 eral of the other subspecies in the field. The discovery of the typ- 

 ical M. mexicanus in Arizona and Southern California by Mr. W. M. 

 Mann, Mr. Leonard and myself brings all of the known species, 

 subspecies and varieties of the genus within the confines of the 

 United States. The separation of these from the Old World 

 forms, till recently regarded as Myrmecocysti, but now placed in 

 Forster's genus Cataglyphis by Emery and Forel, is also an im- 

 portant step in advance, as is also the recognition by the former 

 authority of the fact indicated in my former paper that Myrme- 

 cocystus is closely allied to the circumpolar genus Lasius, whereas 

 Cataglyphis is more intimately related to another circumpolar 

 genus, Formica. These diverse relationships of the New and Old 

 World genera are most clearly seen in their respective males. An 

 unsolved problem is still presented by some of the small species 

 of Myrmecocystus and Formica of the subgenus Proformica, such 

 as M. luguhris Wheeler of Arizona and P. emmoe Forel of Algiers, 

 which resemble each other in the most extraordinary manner. 

 This resemblance, however, may be due to convergence of habit, 

 as both are desert ants. ' Mr. Leonard has found that M. melliger 

 lomaensis has replete, or "honey pot" workers, like the typical 



1 Contributions from the Entomological Laboratory of the Bussey Institution, Harvard 

 University, No. 60. 



2 Honey Ants, with a Revision of the American Myrmecocysti. Bull. Amer. Mus. Nat. 

 Hist. XXIV, 1908, pp. 345-397, 28 figs. 



'The Honey Ants of Point Loma, California. Trans. San Diego Soc. Nat. Hist. I, No. 3, 

 1911, pp. 85-113, 6 figs. 



