46 



William Morton Wheeler 



antennae to establish an independent genus for its reception, but 

 although Monomorhim is made up very largely of species with 12-jointed 

 antennae in the worker and female phases, a few of the species 

 {M. orientale Mayr and M. atomiis Forel) have 11 -jointed and one 



{M. dccamerum Emery) even has 

 10-jointed antennae. As the name 

 gracilliynum is preoccupied in the 

 genus Mouomorium by a species des- 

 cribed by F. Smith in 1861, it be- 

 comes necessary to give the amber 

 species a new name. 



1 9 workers in the Geolog. Inst. 

 Koenigsberg Coll. are referable to 



this form, namely: No. 84/3736, No. 

 Y\gAo. Monom^h^muyria^^^ ^^^^^^^ ^^p^)^ g 252, 



B 18 665, B 18880, B 14742, XX 

 B 301, B 19191, B 19998 (two workers in one block), XXB 607, 

 XXB 594, XXB 1054, and six without numbers. One of the num- 

 bered specimens is in the same block as a worker of Iridomyrmex 

 geinitzi Mayr. There are also five workers in the Klebs Coll. namely 

 K 4274, K 4269, K 1031, K 948 and K 2646. 



M. mayrianum is very similar to M. pilipes, but besides having 

 11-jointed antennae, it is smaller (1,5 — 1,8 mm), the mesoepinotal con- 

 striction is less pronounced, the epinotum is less angular, with a more 

 rounded and convex base and the petiolar node seems to be less com- 

 pressed antero-posteriorly and of about the same size and shape when 

 seen from above as the postpetiole. The sculpture, pilosity and color 

 are very much like those of M. pilipes. 



Tribe Solenopsidiini Emery. 

 Genus Erebomyrma Wheeler. 



Mrebomyrina antiqua (Mayr). 



Pheldologpion nntiquwi Mayr, Beitr. Naturk. Preiips. T, 1868, p. 03, Taf. V, Fig. 95, 96, 9. 

 Aeromyima antiqua Emery, ]\rem. Accad. Sci. Bologna (5) I, 1891, p. 577 9; Dalla 



Torre, Catalog. Hymen. VII, 1893, p. 78; Handlirsch, Foss. Insekt. 



1908, p. 872. 

 Aeromyrma sp. Wheeler, Ants, their Structure, Development and Behavior, 1910, 



p. 163, Fig. 92, cT. 



Worker (Fig. 16a and b). Length about 2 mm. 

 Closely resembling the worker of E. longi Wheeler in shape. 

 Head rather large, subrectangular, somewhat longer than broad. 



