A NEW GENUS OF HYPOG/EIC ANTS FROM TEXAS. 145 



Described from numerous workers and males and four females 

 from Denton, Denton County, north Texas. 



The genus Erebomyrma is to be placed in the Myrmicine tribe 

 Solenopsidii, which is known to embrace the following genera : 

 Solenopsis Westwood (cosmopolitan) ; Diplomorium Mayr (South 

 Africa) ; Acromyrma Forel (Madagascar) ; Oligomyrmex Mayr 

 (India, Australia) ; Carebara Smith (Africa, Australasia) ; Trano- 

 pelta Mayr (South America) ; Lophomyrmex Emery (India) ; and 

 Plicidologeton Smith (India and Australasia). 1 With the excep- 

 tion of the first and last, these genera are represented each by 

 only one or a few species, and in some cases the sexual forms 

 are imperfectly known. Of Tranopclta the workers are unknown, 

 unless the workers from Paraguay mentioned by Mayr (Sued- 

 afrikanische Formiciden, 1901, p. 17) as having a distinctly 

 3 -jointed antennal club, 3 -jointed maxillary palpi and very small 

 eyes, belong to this genus. In view of these facts a future re- 

 vision of the tribe Solenopsidii may lead to modifications in the 

 definition of the genera including the one described in this paper. 

 The genera Aeromyrma, Oligomyrmex, Pheidologeton and certain 

 species of Solenopsk are characterized by having highly dimorphic 

 workers. In many cases these are connected by a more or less 

 complete series of intermediate forms in the same nest (e. g., 

 Pheidologeton, Solenopsis geminatd). Erebomyrma agrees with 

 Diploittorium, Carebara and most species of Solenopsis in having 

 workers of one caste only, and these are extremely diminutive as 

 compared with the males and especially the females. Erebo- 

 myrma is evidently most closely related to Solenopsis, Diplo- 

 morium and Acromyrma, but differs from the two former in hav- 

 ing the epinotum armed and from the latter in having 1 1- instead 

 of lo-jointed antennae, and in the absence of any dimorphism in 

 the workers. The latter character is variable, however, since in 

 one genus (Solenopsis] it is absent in most of the species, though 

 highly developed in others. The female of Erebomyrma is colored 

 and sculptured much like the female of the African Carebara vidua 

 Smith, while the male seems to have many points in common 

 with the male of Tranopclta. It is probable that Erebomyrma 



1 The genus Melissotarsus Emery, formerly supposed to belong to this group of 

 genera, is now placed among the Ponerinae by Emery. 



