428 bulletin: museum of comparative zoology. 



North and Middle Europe. 



According to Forel, this variety is usually smaller than the typical 

 rufa and pratensis, more like the former in pilosity and more like 

 the latter in color, but the reverse conditions are also found. The 

 formicaries, too, are intermediate in all respects. 



23. Formica rufa rufa var. santschii, nom. nov. 



F. rufa var. alpina Santschi, Bull. Soc. ent. France, 1911, p. 349, 1 fig., ^ ; 

 Forel, Rev. Suisse zool., 1911, 19, p. 457; Emery, Deutschr.ent. zeitschr., 

 1912, p. 672. 



Worker. Differing from the typical rufa in having the head pro- 

 portionally longer and narrower (one fourth longer than broad), the 

 scapes longer and extending further beyond the posterior corners 

 of the head, the thorax narrower, the pro- and mesonotum more con- 

 vex and the gaster a little larger. In size, color, and pilosity like the 

 typical form. 



Mountains north of Sondrio, Northern Italy (G. Valerio). Also 

 in Great Britain, according to Donisthorpe, and Norway, according to 

 Forel. 



Santschi believes that this variety of rufa may prove to be merely 

 an abnormality produced by entoparasitism of Mermis or Pelodera 

 or by ectoparasitism of other insects. The name alpina is preoccupied 

 for a variety of F. adamsi Wheeler. 



24. F. rufa pratensis Retzius. 



F. pratensis Retzius, Gen. & spec, ins., 1783, p. 75, ^ ; Roger, Verz. Formic, 

 1863, p. 13; Ern. Andre, Rev. mag. zool., 1874, ser. 3, 2, p. 184; Forel, 

 Bull. Soc. Vaud. sci. nat., 1875, ser. 2, 14, pt. 75, p. 58, 61; Ern. Andre, 

 Spec. Hymto. Europe, 1882, 2, pt. 14, p. 184, 189, S 9 cP; Mayr, 

 Fedtschenko's Turkestan. Formicid., 1877, p. 6; Lubbock, Ants, bees, 

 wasps, ed. 5, 1882, p. 441; Forel, Ann. Soc. ent. Belg., 1886, 30, p. 136, 

 138; Wasmann, Deutsch. ent. zeitschr., 1887, 31, p. 109; Forel, Ann. 

 Mus. St. Petersbourg, 1904, 8, p. 385. 



F. rufa Christ, Naturg. ins., 1781, p. 510, pi. 60, f. 7, 9 d'; Huber, Recherches 

 moeurs fourm. indig., 1810, p. 320, ^ 9 c?'. 



F. congerans Nylander, Acta Soc. Fennica, 1846, 2, p. 906, ^ ; Ibid., 1849, 3, 

 p. 26, 30, cf ; Torster, Hymen, stud., 1850, 1, p. 17, ^ 9 cf ; Mayr, Verh. 

 Zool. bot. ver. Wien, 1855, 5, p. 332, ^ 9 cf; Europ. Formicid., 1861, 

 p. 46-48, S 9 d'; F. Smith, List Brit. anim. Brit, mus., 1858, pt. 6, p. 2, 

 pi. 3, f. 1, 7-9. 



