1903.] NATURAL SCIENCES OF PHILADELPHIA. 233 



the base of the first segment yellow. Antennae and legs yellow, club 

 and sometimes also the scape of the former, infuscated. 



Male. — Length 3.2 mm. 



Mandibles dentate, touching each other with their blades. Antennae 

 12-jointed, scape about as long as the first three joints of the funiculus 

 together; funiculus from the second joint to the end of uniform thick- 

 ness, filiform; second joint a little shorter than the third, shorter, in 

 fact, than anj^ of the succeeding joints. Instead of spines or teeth, 

 the epinotum bears two indistinct elongate swellings. Radial cell of 

 wings short and closed. 



Mandibles rather smooth and shining, with scattered punctures 

 near their inner edges. Clypeus moderately shining and very deli- 

 cately longitudinally rugose. Cheeks and region between antennal 

 insertions and eyes sharply striated longitudinally; front with delicate 

 longitudinal rugae; vertex finely reticulate punctate. Thorax rather 

 smooth and shining, median and posterior portions of mesonotum finely 

 longitudinally rugose and in part obliquely. Petiole, postpetiole and 

 gaster smooth and shining. 



Pilosity sparse, tibiae without suberect hairs. 



Blackish-brown, pedicel and gaster darker. Mandibles, antennae 

 except the brown scape, joints of legs, tarsi, and in part also the joints 

 of the pedicel, yellow or reddish-yellow. Wings clear, hyaline. 



Type locality: "Pennsylvania" (Schaum). 



Additional localities: District of Columbia (Pergande); Beatty, 

 Pa. (Schmitt); Westville, N. J. (Schmitt) ; Austin, Tex. 



In the locality last mentioned I have occasionally taken the 

 workers of L. Schaumi running on the bark of large willows (Salix 

 nigra). 



7. Leptothorax fortinodis Mayr. 



L. fortinodis Mayr, Ver. Zool. bot. Ges. Wien, XXXVI, 1886, pp. 451, 452. 



? ?. 

 L. fortinodis Dalla Torre, Catalog. Hymenopt., "\ II, 1893, p. 124. 

 L. fortinodis Emery, Zool. Jahrb. Abth. f. Syst., VIII, 1894, pp. 318, 321. 



Worker (PL XII, fig. S).— Length 2.5-3 mm. 



Head somewhat longer than broad, sides subparallel, occipital border 

 nearly straight. Eyes moderately large and convex. Mandibles 

 5-toothed. Clypeus convex, its anterior border broad and rounded. 

 Antennae 11-jointed; scape reaching to midway between the eye and 

 the posterior angle of the head; funiculus terminating in a 3-jointed 

 club; first funicular joint as long as joints 2-4 together; joints 2-5 

 broader than long, 6 and 7 as long as broad; terminal joint somewhat 



