The Ants of the Baltic Amber. 125 



addition- to 49 of the 53 specimens studied by Mayr in the Geolog. 

 Inst. Koenigsberg Coll. including the single gynetype and two andro- 

 types, I have examined 1022 specimens. These are distributed as 

 follows: 731 workers, 2 females and 68 males in the Geolog. Inst. 

 Koenigsberg Coll. (B 1898, B 19090, B 19425, B 19067, B 18779, 

 B 19730, B 19194, B 18584, B 16592, B 18681, B 18834, XXB 1416, 

 B 19026, B 14153, B 18737, B 18188. B 18335, B 5069 etc.), 118 

 workers and 18 males in the Klebs Coll. (K 4778, K 1690, K 4770, 

 K 4459, a 73, « 110, K 4774, K 1052, a 107, K 875, a 135, K 4060, 

 K 1056, K 768, a 4, « 49, K 1677, K 1062, K 5179 etc.); 39 workers 

 and one male in the Berlin Museum (306, 280, 302, 301, 299, 297. 

 292, 291, 298, 290 etc.) 6 workers in the Brussels Museum (205, 207, 

 210, 226 and 2 without numbers) and 30 workers in the Haren Coll. 

 <26, 220, 253, 373, 857, 855, 589, 442, 863, 927, 979, 983 etc.). There 

 are also two worker cocoons (IIB 313 and B 5157) containing pupa^ 

 of this ant in the Geolog. Inst. Koenigsberg Coll. 



Formica horridaf sp. nov. 



Worker (Fig. 59). Length 3,5—4,5 mm. 



Allied to F. cinerea Mayr. Head a little longer than broad, 

 narrower in front than behind, with rounded sides and posterior cor- 

 ners and straight posterior border. Eyes large, moderately convex, 

 Clypeus sharply carinate, its anterior border angulary projecting in 

 the middle. Antennal scapes straight, not curved even at the base, 

 of nearly uniform thickness except at their insertions, and extending 

 about ^/g their length beyond the posterior corners of the head; funi- 

 cular joints 2 — 10 subequal in length but the more distal joints broader. 

 Thorax shaped much as 

 cinerea. Petiole rather 

 narrow, the node somewhat 

 broader above than below, 

 with straight sides and 

 broadly rounded, rather 

 sharp superior border. 



Body shining, finely 

 shagreened and super- 

 ficially punctate. t,- -r, r. • , •, nr , 



•i^ I"ig. ;)9. Formica horrida sp. nov. Worker. 



Hairs erect, long, 

 stiff, coarse and abundant, covering the body, legs and antennal scapes; 

 longest on the gaster; on the funiculi very short and oblique. Pubes- 

 cence on body very short and dilute. 



