292 <■■ H Osten Hacken: 



bifurcation of the äccond and third veins takes place almost immcdiatcly 

 after the origin of the secoiid; in Apiocera and the Asilidae the prae- 

 furca is longer. — 3. The majority of the Midaidae have only four 

 posterior cells, oue of the veins, issuing from the discal cell being ob- 

 literated; Apiocera, like the Asilidae, has five posterior cells. Those 

 few Midaidae, that have five posterior cells (the australian genus Dio- 

 chlistus and Triclonus and the chiliau Mitrodetus), still differ from 

 the Asilidae and from Apiocera in the charactgristic sbape of the discal 

 cell and the shortness of the praefurca. 



It seems therefore that when Schiner insisted on the venation as 

 a proof of the relationship öf Apiocera with the Midaidae, he had not 

 given sufficient attention to the subject. 



The alulae of Apiocera are large, the tegulae have long, soft, 

 wooly cilia, like those of Proctacanthus and Erax. The cilia in Midae 

 form a short, stiff friuge; those of Leptomidas are microscopic. 



To sum up; Apiocera diflfers from the Midaidae: 



1, In the presence of ocelli; 2. In the presence of macrochetae 

 on head and thorax; 3. In the structure of the scutellum; 4. In the 

 structure of the legs; 5. In the presence of palpi; 6. In the venation; 

 7. In the structure of the $ forceps 5 8. In the structure of the an- 

 tennae; 9. In the usual character of the coloring. 



An d in a^^thesecharacters Apiocera is like the Asilidae. 



The real differences between Apiocera and the Asilidae would thus 

 be reduced to the shortness of the face, to the shape of the palpi, and 

 to the course of the first vein issuing from the discal cell. Would we 

 be justified in introdücing a new family on the strength of these 

 differences, and notwithstanding the overwhelming coincidences between 

 Apiocera and the Asilidae? I think not. 



We may therefore conclude by saying that Apiocera is an Asilid 

 adapted to peculiar and as yet unknown conditions of life. Its some- 

 what weaker and less bristly legs may indicate that its prey is perhaps 

 easier to catch and to hold; the weaker proboscis, ending in fleshy lips, 

 may prove that the prey is easier to pierce etc. What the purpose 

 of the spoon-shaped palpi and of the short, beardless face may be, is 

 more difficult to foreshadow. 



It strikes me, as another result of my comparisou between the 

 Asilidae and the Midaidae, that the relationship between those families 

 is somewhat less close than was heretofore supposed. 



The relationship to the Therevidae, suggested by Macquart and 

 Brauer, rests principally on the shortness of the face. But the short 

 face of Thereva depends more on the oblique emargination of the raouth 

 than on the low Insertion of the antennae. The venation of Thereva, 

 on account of the shortness of the first longitudiual vein, belongs to a 



