The Ants of the Baltic Amber. 67 



distinguished from all the preceding species by its 11-jointed antennae. 

 It does not closely resemble the recent L. (MychothoraxJ acervorum, 

 except in this number of antennal joints and the mesoepinotal con- 

 striction. 



Genus Stiphi^otnyrtnex, gen. nov. 



Worker. Head rather large, convex above, flattened below, 

 with small eyes, situated in front of the middle. Ocelli absent. 

 Mandibles rather short, convex, 4-toothed. Maxillary palpi 4-jointed, 

 labial palpi apparently 3-jointed. Clypeus bicarinate in the middle, 

 short and depressed on the sides. Antennal fovese large, deep and 

 circular, not covered by the frontal carina?, which seem to be very 

 poorly developed. Antenna? 12-jointed, rather robust, with a 3-jointed 

 club about as long as the remainder of the funiculus. Thorax very 

 short, not longer and decidedly narrower than the head, slightly con- 

 stricted on the sides in the mesoepinotal region but without pro- 

 mesonotal and mesoepinotal sutures. Epinotum armed with a pair of 

 long and powerful spines. Petiole and postpetiole narrow, the former 

 with a short, indistinct peduncle, the latter constricted behind. Gaster 

 subelliptical, somewhat larger than the head, slightly narrowed in 

 front, with a very large basal segment. Legs long and robust, the 

 femora and tibiae clavate; middle and hind tibiae with simple spurs. 

 Genotype Stigmomyrmex rohustus Mayr, 



Stiphromyr^nex robustus (Mayr). 



Stigmomyrmex {?) robustus Mayr, Beitr. Naturk. Preuss. I, 1868, p. 97, Taf. V. 



Fig. 101, $. 

 Stigmomyrmex robustus Dalla Torre, Catalog. Hymen. VII. 1893, p. 78: Hand- 



LIRSCH, Foss. Insekt, 1908, p. 873. 



Worker (Fig. 27). Length about 3,5 mm. 

 Head nearly as broad as long, with convex, rounded sides and 

 rather deeply excised posterior border. Mandibles short and convex, 

 with two blunt, subequal apical and two smaller basal teeth. An- 

 tennal scapes curved at the base and reaching about half the distance 

 from their insertions to the posterior corners of the head; first funi- 

 cular as long as the three succeeding joints together; joints 2 — 7 much 

 broader than long, joint 8 nearly as long as broad, terminal as long 

 as the two preceding subequal joints. Thorax rounded and convex in 

 front, narrower anteriorly, with subparallel sides behind, the latter region 

 embracing the epinotum, the former the combined pro- and mesonotum. 

 In profile the dorsal outline of the whole thorax to the base of the 



