wheeler: ants of the genus formica. 489 



Indiana: Tippecanoe Lake (W. S. Blatchley). 

 Nova Scotia: Digby (J. Russell). 



Described from a large number of specimens, all agreeing in the 

 characters noted above. 



72. F. EXSECTA EXSECTA Ny lander. 



F. exseda Nylander, Acta Soc. Fennica, 1846, 2, p. 909, pi. 18, fig. 20, ^ 9 cT ; 

 Ann. sci. nat. ZooL, 1856, ser. 4. 5, p. 63, pi. 3, fig. 7, t^ 9 cf ; Forster, 

 Hymen, stud., 1850, 1, p. 23, ^ 9 d' ; Mayr, Verb. Zool. hot. ver. Wien, 

 1855, 5, p. 340, y 9 d"; Europ. Formicid., 1861, p. 46-48; Forel, Denks. 

 Schweiz. gesell. Naturw., 1874, 26, p. 51, ^ 9 cf; Em. Andre, Spec. 

 Hym6n. Europ., 1882, 2, pt. 14, p. 178, 185, 188; Dalla Torre, Catalog. 

 Hymen., 1893, 7, p. 195; Ruzsky, Formicar. Imper. Ross., 1905, p. 353, 

 figs. 67, 68; Emery, Deutsch. ent. zeitschr., 1909, p. 189, fig. 5; Ibid., 

 1912, p. 672. 



Worker. Length 5-7.5 mm. 



Mandibles 8-toothed, with additional indistinct denticles on the 

 basal margin. Head longer than broad, narrowed somewhat at the 

 posterior corners so that it is here no broader than at the anterior 

 border; posterior border deeply excised. Front convex; clypeus 

 sharply carinate, without a distinct, transverse depression behind its 

 anterior border. Maxillary palpi long, 6-jointed. Pro- and mesono- 

 tuni not very convex; mesoepinotal constriction shallow, broad at 

 the bottom. Spiracles of metanotum prominent. Epinotum rounded, 

 without distinct base and declivity. Petiole narrow, strongly com- 

 pressed anteroposteriorly, its superior margin thin, sharp, and very 

 deeply excised. 



Opaque or slightly shining. Mandibles finely striated and coarsely 

 punctate. 



Hairs very sparse, distinct on the gaster, where they are short and 

 obtuse. Pubescence yellow, moderately abundant, especially on the 

 head, prothorax, and gaster, longest on the cheeks. Eyes hairless. 



Red or sordid yellowish red; clypeus and appendages darker, postero- 

 dorsal portion of head, a large spot on the pronotum and often also 

 a small one on the mesonotum, brown; gaster blackish brown, base of 

 first segment red or yellow. 



Female. Length 8-9.5 mm. 



Resembling the worker. Anterior border of clypeus straight in the 

 middle. Thorax with flattened mesonotum and scutellum. Petiole 

 much broader, flatter, and more deeply excised than in the worker. 



Sculpture much as in the worker. Hairs more abundant especially 

 on the mesonotum, posterior border of pronotum, and front of head. 

 Pubescence longer but sparse, conspicuous both on the body and 

 appendages. 



