The Ants of the Baltic Amber. 
135 
behind than in front, with straight posterior border and less convex 
sides. Ocelli present, minute. Antennal scapes reaching further beyond 
the posterior Corners of the head. Mandibles 8-toothed. Pronotuni 
and epinotum less convex, mesoepinotal constriction somewhat less 
pronounced. Sculpture and pilosity as in the worker major but color 
more often pale brown or yellowish. 
Described from 33 specimens, distributed as follows: 9 major 
and 17 minor workers in the Geolog. Inst. Koenigsberg Coli. (XB 948, 
XXB 121, 11216/834, XXB 1085, B 18 826, XXB 778, B 19 212, 
B 18 995, XXB 485, XXB 867, XXB 7177, B 19479, B 19 712, 
14374/1015, XXB 1022, B 19 742 and 10 without numbers); 4 major 
and 2 minor workers in the Klebs Coli. (K 6405, K 5619, K 1047, 
« 130, a 175, a 72) and one major worker in the Haren Coli. (976). 
Among the specimens included under the description of the worker 
minor, the head varies in size, so that the worker of this species is 
really polymorphic and not dimorphic. The small eyes and pale color 
would seem to indicate that it was nocturnal or crepuscular. It is 
very easily recognized among the amber Camponotince by its small 
eyes, peculiar pilosity and the shape of the thorax and petiole. I refer 
it to the genus Pseudolasius though in the structure of the thorax 
and the position of the eyes it differs greatly from the only species 
of this genus known to me, namely Ps. binghami Emery of India. One 
of the recent species, however, Ps. mayri Emery of Java, Sumatra and 
Borneo, has a deeply constricted thorax like Ps. boreus, judging from 
Emery’s description, but the apical mandibular border is very oblique. 
The eyes, which have only about 5 facets and must therefore be even 
more poorly developed than those of boreus, are placed a little in 
front of the middle of the head. In other respects the two species 
must be rather similar. It is apparent from Emery’ s recent re vision 
of Pseudolasius (Mem. Soc. Ent. Belg. LV, 1911, p. 219) that none of 
the 13 species which he enumerates is at all satisfactorilv known. 
Of this number 12 are peculiar to the Indomalayan Region and only 
one to Africa. The occurrence of a species in the Baltic amber shows 
that the genus had a much wider distribution during early Tertiary times. 
Tribe Camponotini Forel. 
Genus Drymomyrmex, gen. nov. 
Female. Allied to Aphomomyrmex Emery. Body rather long 
and narrow. Head subrectangular, decidedly longer than broad, as 
broad in front as behind, with straight sides and posterior border, 
with the moderately large, flattened eyes at the middle of its sides. 
