APPLE LEAVES, APHIS ATTENDANTS — SHORT-HORNED STEM-EYE. 69 



ing in an oval knob) yellowish white. Abdomen dusky, clothed with a short 

 black beard, hind edges of the segments pale dull yellow. Legs pale yellow, 

 with a fine black beard, and the spine-like bristles at the end of the shanks 

 black. Wings iridescent, smoky brown on the outer and apical margins, hya- 

 line towards the axilla, the space between divided into numerous square hya- 

 line spots by dusky longitudinal stripes, one stripe being placed in the middle 

 of each cell, and sending short, transverse branches to the veins at regular in- 

 tervals; veins and veinlets black. 



Nearly related to the flies which we have been considering are 

 those very singular ones, called Stem-eyed flies from having 

 straight horn-like processes extending outwards from the sides of 

 the head, upon the ends of which the eyes are inserted. These 

 form the old Linneeari genus Diopsis. About a dozen species are 

 known, all inhabiting tropical Africa and the East Indies, with 

 one exception — the Short-horned Stem-eye of this country, origi- 

 nally described by Mr. Say under the name of Diopsis brevicornis. 

 As this species has the tubercles on which the eyes are inserted 

 •quite short, their length being less than their breadth, whilst in 

 the other species they are much longer, and cylindrical, Mr. 

 Say, in the third volume of his American Entomology, plate 52, 

 proposed for it a distinct genus, which he named Sphyracephala. 

 The European entomologists, however, ignore this genus and con- 

 tinue to arrange our species in the old genus Diopsis. I am 

 somewhat surprised at this. A specimen from Senegal, ticketed 

 D. thoracica by Macquart, for which and numerous other speci- 

 mens of Diptera, I am indebted to M. Bigot, of Paris, indicates 

 the foreign species of this tribe to be quite unlike ours in their 

 general appearance. Having recently taken a second species 

 closely related to the brevicornis, I think our two American spe- 

 cies must be ranked as generically distinct from those of the 

 •old world. In addition to the extreme shortness of the ocular 

 protuberances and the minuteness of the projecting points to the 

 scutel and on the sides of the thorax towards its base, they are 

 further distinguished by having an anastamosis between the cos- 

 tal or anterior marginal vein and the sub-marginal or short vein 

 which runs into the anterior margin near the middle, this anas- 

 tamosis taking place a short distance before the two veins unite. 

 In the new species which I have alluded to a dusky spot or short 

 band extends from this anastamosis across the two basal cells of 

 the wing, and a second band half way from this to the tip 



