306 E. T. CRESSON, JR. 



Ithaca, N. Y., 1; Sea Cliff, L. I., 1; Falls Church, Va., 2 

 (all coll. Banks). Taken June to August. 



A rather robust species, distinguished by its black antennae, 

 yellow humeri and halteres, shining abdomen and yellow 

 legs with black banded femora. A specimen from Amsden, 

 Vt. {Johnson, B. S. N. H.), is very similar, but the oviposi- 

 tor is abruptly terminating the base (Fig. 88), and the mid- 

 dle femora are without the yellow hairs. Wings as in Fig. 

 147. 



30. P. alpinus n. sp. 



9 . Similar to sororius, but smaller. Antennae more finely acumi- 

 nate (Fig. 14). Femora black, except bases and apices; tibiae and 

 tarsi dirty yellow, former more or less tinged with brown. Ovipositor 

 much longer and slender, curved down, extending to base of abdomen, 

 abruptly terminating its elongate base, which has a more or less de- 

 veloped tubercle above next to venter of abdomen (Fig. 86). Length, 

 3.7 to 4.5 mm. ; wings (Fig. 170) , 4.2 to 5.0 mm. 



Type.—m. Equinox, Vt., June 5, '10 (Figs. 14, 86, 170, 

 Johnson, B. S. N.H.). 



Paralyses.— Mt. Ascutney, Vt. (1, Johnson, B. S. N. //.); 

 Mt. Washington, N. H. (1, Slosson, B. S. N.H.). Taken 

 June to July. 



Although closely related to sororius in general form and 

 color, it is distinctly separated by the form of the ovipositor. 



31. P. constrictus Banks, n. sp. 



"o 71 . Face and front silvery pollinose; antennae black, third joint 

 only short pointed below, arista swollen at base (Fig. 32); occiput 

 silvery pollinose on sides, dull black above ; thorax dull brown-black 

 above, humeri yellow, pleurae silvery pollinose ; poisers slightly 

 brownish on the tips; abdomen shining black, punctate, with fine 

 short hairs above, lower sides gray-pollinose, it is rather slender, the 

 sides subparallel, and the segments narrowed at base and tip, so that 

 they have a constricted appearance, hypopygium small, with a broad 

 apical slit, slightly to the right side; legs pale yellowish, tips of tarsi 

 blackish, a short blackish mark on upper anterior middle of front 

 femora, and on lower anterior middle of middle femora, hind tibia 

 only slightly curved. Wings hyaline (Fig. 178), stigma long, brown, 

 veins blackish, except at base, small cross-vein at end of basal third 

 of cell, but plainly beyond end of auxiliary vein, the fourth longi- 

 tudinal has an appendix at end of basal fourth beyond end of cell, it 



