Lonchopteridae. 11 



with regard to time, and it is not improbable that also the imago 

 may hibernate. According to de Meijere the eggs are white, oval, 

 0,6 mm long and 0,25 mm in diameter; the shell is structure-less. 



A very curious feature is found in one species, furcata; in this 

 species the males are very rare; w^hile the female is common and 

 may be found in great numbers on the localities where it occurs, 

 there are in all known, I think, about six males. For this reason de 

 Meijere Ihinks (Tijdschr. v. Entom. XLIX, 1906, 49) that this species 

 propagates mainly by Parthenogenesis, and he supports this opinion 

 by the shape of the receptacula seminis; these are in L.lutea long, 

 and spermatozoa are often found in them ; in furcata on the contrary 

 the receptacula are short, and the author never found spermatozoa in 

 them. This faet would be rather unique among the Diptera. 



The species of Lonchoptera are small flies, characteristic by the 

 shape of their wings; they occur on humid piaces, often at horders 

 of water and generally in great numbers. 



Of the genus now 7 palæarctic species are known after de Meijere's 

 revision; 3 have been found i Denmark. 



Tåhle of Species. 



1. Front femora with only one bristle above near apex; middle 

 femora in the male with 2 — 3 bristles below in the middle; 

 wings somewhat strongly brown ; rather large, always dark 



species 3. tristis. 



— Front femora with three bristles above near apex ; middle 

 femora in the male without bristles below; wings only yel- 

 lowish; smaller, often more or less pale species 2. 



2. Vertical bristles all, or at all events the inner, nearly always 

 black; front libiæ without posterior bristle and middle tibiæ 

 without ventral bristle; postocular bristles yellow; anal vein 

 generally terminating below the base of the discai fork ... 1. lutea. 



— Vertical bristles all yellow ; front tibiæ with a posterior bristle 



and middle tibiæ with a ventral bristle ; some of the upper ^ 



postocular bristles generally black ; anal vein terminating behind 



the base of the discai fork 2. furcata. 



1. L. lutea Panz. 



1809. Panz. Faun. Germ. GVIII, 20, 21. — 1824. Meig. p. p. Syst. 

 Beschr. IV, 107. - 1848. Zett. p. p. Dipt. Scand. VII, 2802, 1. — ?1862. 

 Schin. F. A. I, 243. — 1903. Kat. palåarkt. Dipt. p. p. II, 353. — 1906. 

 De Meij. Tijdschr. v. Entom. XLIX, 64, 1, PI. I, Fig. 2, 5 — 6, PL II, Fig. 

 20—22. — Dipsa furcata Fall. p. p. 1823. Dipt. Suec. Phytom. 1. — 

 L. flavicauda Meig. 1824. 1. c. 107. — 1903. Kat. palåarkt. Dipt. II, 353. 



— L. lacustris Meig. p. p. 1824. 1. c. 107. — 1903. Kat. palåarkt. Dipt. 

 p. p. 353. — L. riparia Meig. p. p. c?, 1824. 1. c. 108. — 1903. Kat. 

 palåarkt. Dipt. p. p. 353. — L. rivalis Meig. p. p. 1824. 1. c. 108. — 



