Ptychomyia. 345 



reflected below. Antennæ inserted high above, near upper margin 

 of the eye, third joint about six times as long as second; arista with 

 second joint elongated. Thorax a little rectangular; four postsutural 

 dorsocentrals, and three præ- and three postsutural acrostichals; 

 a præsutural intraalar bristle. Scutellum with three marginal bristles 

 on each side, the apical wanting. Three sternopleural bristles. Ptero- 

 pleura slightly hairy, with a single bristle above. Abdomen ovate; 

 excavation on second segment reaching hind margin ; there are discai 

 and marginal bristles, or generally only marginal; second segment 

 with a pair. Legs not long; hind tibiæ with unequal anterodorsal 

 bristles; claws and pulvilli in male only slightly elongated; front 

 tarsi in female simple. Wings with first posterior cell open a little 

 before apex of wing; discai angle about rectangular with an indica- 

 tion of a veinlet; posterior cross-vein near middle between medial 

 cross-vein and angle; bristles at base of cubital vein reaching more 

 or less towards medial cross-vein; no costal spine. 



The species is parasitic on various Heterocera and especially on 

 a number of Tenthredinids ; it belongs to Pantel's group 1, and the 

 larva forms a primary breathing hole. 



Only one certain European species is known, also occurring in 

 Denmark. 



1. P. selecta Meig. 



1824. Meig. Syst. Beschr. IV, 377, 237 {Tachina) et 1838. VII, 249, 13 

 {Degeeria). — 1862. Schin. F. A. I, 535 (Degeeria). — 1889. B. B. Denkschr. 

 Akad. Wiss. Wien, LVI, 89, Tab. II, Fig. 23. — 1907. Kat. palåarkt. Dipt. III, 

 300. — 1921. Baer, Zeitschr. f. angew. Ent. VII, 159. — 1924. Stein, Arch. f. 

 Naturgesch. 90, 6, 102. — Tachina parallela Meig. 1824. I. c. IV, 377, 238 et 

 1838. VII, 249, 1 {Degeeria). — 1900. Stein, Entom. Nachricht. XXVI, 145. 



— Tachina tincta Meig. 1824. 1. c. IV, 378, 239 et 1838. VII, 249, 7 {Metopia). 



— 1844. Zett. Dipt. Scand. III, 1030, 20 et 1849. VIII, 3228, 20 et 1859. XIII, 

 6080, 20 {Tachina). — Roeselia convexijrons Pand. (nec. Zett.) 1896. Rev. 

 Entom. XV, 44, 3. — 1907. Villen. Ann. Soc. Ent. de Fr. LXXVI, 388. 



Male. Frons above about as broad as the eye. Orbits yellowish, 

 blackish above; cheeks greyish silvery; jowls grey; frontal stripe 

 velvet black or a little brownish. Vibrissæ not numerous, but some- 

 what strong. Orbits and jowls with black hairs. Occiput dark grey, 

 with whitish hairs, and with some black hairs behind postocular 

 bristles. Antennæ black; arista distinctly thickened in basal third 

 or a little more. Palpi black. Thorax black, somewhat shining, 

 yellowish grey pruinose, especially in front and at the sides, with 



