254 Tachinidae. 



and in America it has been bred from other terrestrial Isopods; it is 

 also recorded from Asopia farinalis, and below I mention it from 

 Epeira-eggs. The species helicivora is recorded from Helix conspurcata. 

 Of the genus about 4 European species are recorded, one occurring 

 in Denmark, and only this well known. 



1. M. roralis Linn. 



1758. Linn. Syst. Nat. X, 597 et 1767. XII, 2, 993, 85, S {Musca). — 1762. 

 O. F. Mull. Faun. Fridr. 83, 739 [Musca). — 1805. Fabr. Syst. Antl. 304, 102 

 [Musca). — 1820. Fall. Dipt. Suec. Rhizom. 7, 7 [Ocyptera). — 1824. Meig. Syst. 

 Beschr. IV, 284, 79 [Tachina) et 1838. VII, 213, Tab. LXIX, Fig. 46—52. — 

 1844. Zett. Dipt. Scand. III, 1237, 1. — 1862. Schin. F. A. I, 553. — 1889. 

 B. B. Denkscbr. Akad. Wiss. Wien, LVI, 111, Tab. VI, Fig. 121. — 1896. 

 Pand. Rev. Entom. XV, 140, 1. — 1907. Kat. palåarkt. Dipt. III, 460. — 

 1924. Stein, Arch. f. Naturgesch. 90, 6, 181. — Musca grossificationis Linn. 

 1758. Ent. Syst. X, 599 et 1767. XII, 2, 996, 109, ?. — 1805. Fabr. Syst. Antl 

 324, 42 [Tephritis). — M. atra R. D. 1830. Myod. 272, 3. — 1838. Meig. 1. c. 

 VII, 213, 2. — 1862. Schin. F. A. I, 553. 



Male. Frons broad, broader than the eye. Orbits and cheeks 

 black, shining; jowls more or less reddish with the intermediate 

 triangle impressed. Frontal stripe brown or blackish brown. Orbits 

 with few hairs, generally strong and bristly below; cheeks along inner 

 margin with very fine and short hairs, Occiput black, with black 

 hairs. Antennæ black or brownish, short, third joint about as long 

 as second; arista thickened at base. Palpi blackish. Thorax black, 

 shining, sparingly black-haired, the hairs mainly present in the 

 acrostichal, dorsocentral and intraalar regions with bare intermediate 

 spaces. Apical scutellar bristles somewhat small, crossing. Abdomen 

 black, shining, black-haired, with marginal bristles, a pair on second 

 and third and a row on fourth and fifth segment. Fifth sternite 

 roundly incised in apical half. Legs black, rather slightly bristled. 

 Wings blackish or brown, with brown veins; discai angle more or 

 less obtuse, rarely with a veinlet; posterior cross-vein rather near 

 medial cross-vein. Squamulæ blackish brown. Halteres with the knob 

 black, the peduncle yellow. 



Female. Similar, with frons of about the same breadth. Front 

 tarsi more robust than in male. Wings wth the apex below cubital 

 vein milky white, forming a conspicuous spot. 



Length 5 — 5,5 mm. 



M. roralis is common in Denmark ; at Copenhagen, Egebæks 

 Vang, Sletten, Frederiksværk, Korsør, at Sorø; on Lolland at Maribo; 



