86 STRATIOMYID^ 



Surrey, in the earlier part of the last century. Walker says " Very rare ; 

 " has been found in Coombe Wood, Surrey and in Darenth Wood, Kent. 

 " In the British Museum, and in Mr Desvignes' collection (E.)." Donovan 

 figured it in 1813, and said it was taken at Coombe Wood on June 4, 1812, 

 by George Milne, Esq., Kent, and that it had occurred in the woods about 

 Highgate, while Swainson is said to have taken three specimens at one 

 time. Stephens said (Illustrations of British Entomology, Suppl. 27) that 

 he possessed a pair which had been " taken in June in " Coombe Wood." 

 The late Mr J. C. Dale kept a note-book upon British Diptera which is 

 now in the possession of the Hope Museum at Oxford, and in it is the 

 following note concerning this species : " Coombe Wood, Surrey, Trunks 

 "of Trees, June 4, 1812, G. Milne, Highgate, Middlesex." Of the three 

 specimens in Dale's collection one male and one female were labelled 

 " Desvignes' coll.," and on the female was the label " Coombe AYood," but the 

 other female bears no history. It would appear from this that Donovan 

 figured it the year after G. Milne took it. I remember being present at 

 Stevens' Auction Eooms when J. C. Dale bought Desvignes' specimens. 

 The possibility of its having occurred in Britain is rendered probable 

 by the occurrence of a specimen at Venlo in the Netherlands, and 

 through Macquart including it in his Dipteres du Nord de France. It 

 has been bred from the nest of Formica fuliginosa, and a full account 

 has been given by Miirkel in G-ermar's Zeitschrift, v., p. 266 (1844), and 

 Latreille when describing the species in 1809 said " larva in arboribus ? " 

 It has been recorded from Central and Southern Europe. 



Synonymy. — This species was first described by Fabricius in his Systema 

 Entornologica (1775) under the name of Strafimnys ephippucm ; in 1802 Latreille 

 established the genus Ejyhij^pimn, and in 1804 according to the custom of the time 

 renamed the species thoraricum ; an attempt has been made to change the generic 

 name upon theigrounds of its pre-occupation in the Mollnsca and in that case to 

 reinstate the specific name " ephippium^^ but I cannot agree with that because of 

 the reasons I have already stated. 



3. OXYCERA. 



Oxijcera Meigen, Illig. Mag., IL, 265 (1803). 



Handsome black and yellow or black and green flies of 

 moderate or small size ; almost, bare and usually of a black 

 ground colour with conspicuous yellow or green spots and 

 markings, but the pale markings are sometimes so much 

 extended as to become predominant. 



Head broader than deep when seen from in front ; face and frons in the male 

 forming a flat almost equilateral or S(iuat triangle, as the eyes touch on the frons 

 while the jowls are hardly visible, but in the female the frons and face are almost 

 equally wide from the vertex to the mouth ; lower half of the back of the head 

 considerably puffed out and bearing moderately long pubescence ; vertex in the 

 male elongate, with the ocellar space more or less elevated ; proboscis retracted, but 

 with broad sucker-flaps. Eyes touching in the male for a considerable distance, 

 but widely separated in the female ; ranging from being practically bare in both sexes 

 to being densely hairy in the male, and then the eyes of the female may bear some 

 slight pubescence ; in the male the facets on the larger upper part are conspicuously 

 larger and usually abruptly contrasted in size with the small facets on the smaller 

 lower part, and very frequently there is a strong contrast in colour in dried specimens 



