1903,] NATURAL SCIENCES OF PHILADELPHIA. 259 



living "in independent formicaries, in the moss of woods or in the earth 

 of meadows, hke the ordinary species of Leptothorax" (Aim. Soc. Ent. 

 de Belg., Tome XLV, 1901, pp. 389-398). In Texas I have had ample 

 opportunity to observe the habits of this ant, especially in the neigh- 

 borhood of Austin, where it is found making its nests in very sparsely 

 grassy spots among the mesquite and Opuntia thickets. The nests 

 can be found only by carefully tracking foraging workers, as the 

 entrance is a small hole often concealed under a dead twig or a tuft of 

 grass roots. The colonies are hardly more populous than those of 

 other species of Leptothorax. The winged forms appear during the 

 last week in April and the first week in May. The workers run about 

 on the soil in the hot sun as fierce hunters of small insects (Aphids, 

 minute Heteroptera, etc). As they are extremely pugnacious even 

 toward individuals of the same species from other nests, and as I have 

 never found them nesting with Monomorium jninimum, though this 

 species is very common in the same localities, I believe, with Forel, 

 that Pergande's observation must be cjuite exceptional or may even 

 involve some misinterpretation. 



20. Leptothorax (Dichothorax) floridanus Emery. 



L. (D.) floridanus Emerv, Zool. Jahrb., Abth. f. Syst., VIII, 1894, pp. 318, 

 324. ^ . 



According to Emery, the worker of this species (PI. XII, figs. 24 and 

 24a) differs from the preceding in the following characters : The body is 

 more shining, the epinotum smooth and shining above, the mesoepinotal 

 constriction punctulate, subopaque, the petiolar node is narrower, and 

 not impressed above, the postpetiole is hardly ^ again as broad as the 

 petiole and proportionally narrower than in Pergandei. 



Type locahty: Florida (Pergande). 



Additional locality: North Carohna (Forel). 



The differences between the two Dichothorax are so slight that 

 Emery suspected floridanus to be merely a subspecies of Pergandei. 

 I am myself strongly of this opinion, but as I have seen only a single 

 specimen of floridanus, kindly given me by Prof. Forel, I hesitate to 

 reduce this form to subgeneric rank. In my specimen the petiolar 

 node is very decidedly convex when seen from behind, and the epinotal 

 spines are longer and more curved than in any of my specimens of 

 Pergandei. In other respects I can see no differences of importance. 

 Color, pilosity and sculpture are the same in both forms. 



