294 LEPTIDtE 



and bearing a few pale hairs which are almost erect, and from which shorter 

 inconspicuous pubescence extends to the upper eye-angles ; face widening 

 downwards less than in the male ; back of the head more equally pufifed out 

 because the upper part of the eyes is not so much ridged but slopes more 

 gradually to the occiput. Antennae with the two basal joints slightly brownish, 

 and with the bristles on the basal joint shorter and more or less pale. 



Thorax with the humeri conspicuously greyish luteous, and with all the 

 margin of its dorsum and the basal corners of the scutellum brownish luteous. 



Abdomen with alternate black and orange bands, the orange colour 

 rather predominating up to the end of the fourth segment, but after that with 

 only a trace of an orange band rather before the hindmargin of the fifth 

 segment ; sixth segment rather greyish black and hardly one-third as long as 

 the fifth, while the seventh and eighth segments are each only about half as 

 long as the sixth ; pubescence mainly pale but extensively black on the black 

 parts, neither abundant nor conspicuous. Belly orange on the five basal 

 segments except for a blackish band across the middle of the fifth segment, 

 and after that segment more blackish though the hinder parts of the sixth 

 and seventh segments are broadly but obscurely luteous ; eighth segment 

 indistinct ; pubescence inconspicuous and pale. Ovipositor showing a pair 

 of short broad rounded brownish yellow lamellje. 



Legs rather similar to those of the male but the hind femora have the 

 apical blackening more restricted to the upper side ; hind tibiae all dull 

 brownish luteous and not at all dilated ; hind tarsi with the basal joint also 

 brownish luteous and also hardly dilated though long and strong. Pubescence 

 or ciliation very slight except for the abundant minute black bristles, but 

 there is a short ciliation on the hind tibiae which is not so regular or neat as 

 in the male ; " touch-hairs " almost as in the male. Front pulvilli and claws 

 simple. 



Wings, squamfe and halteres as in the male. 



Length about 6 mm. 



*o' 



This species somewhat resembles Zeptis lineola, but may be at once 

 distinguished by the generic characters; L. lineola also has seven 

 gradually decreasing abdominal segments, and its male has a very short 

 genital plate. Any superficial resemblance to a llhyphus is removed upon 

 examining the venation in regard to the forked cubital vein and the closed 

 anal cell. 



A. crassipes was first noticed in England by Mr Henry W. Andrews in 

 fair abundance in some water meadows near Ticehurst Eoad Station in 

 Sussex on July 10, 1900; the specimens generally occurred on the leaves 

 of Alder {Alnvs glutinosa) and were found again in the same locality 

 on July 6, 1901 ; since then it has been found in two or three localities in 

 the New Forest by Dr D. Sharp and Mr C. G-. Lamb, in abundance in a 

 little meadow at Milford on Sea about the end of June 1904, and in the 

 New Park Enclosure in July 1904, and by Mr H. W. Andrews as late as 

 July 23, 1904. It seems to be very little known on the continent, but 

 was recorded by Meigen in 1820 from Marseilles and in 1830 from near 

 Luttich, by Schiner from (probably) Austria, by Coucke from Amersfort 

 in Holland, while I possess a male from Attica and a male from Kowarz's 

 collection taken by Loew at Meseritz in Prussia; it would appear to be 

 widely spread in Europe but occurring in only small colonies. 



Synonymy. — No doubt can arise as to this being Atherix crassvpes of Meigen, but 

 I cannot recognise Rliagio nehulosa of Fabricius in it because according to Meigen 

 that species has the anal cell open • it is however almost certainly Atherix nehulosa 

 of Macquart from North France (which he specially says has the anal cell closed) and 

 of Zetterstedt in liis Note in Dipt. Scand., viii., 2990 (as received from "St Sever" 

 in France). All other descriptions appear to be merely copies. 



