8 ARKIV FÖR ZOOLOGI. BAND 7. NIO 28. 



in which the position of the genital aperture was a more 

 backward one. This is, however, not the case, since in 1905, 

 when establishing the subfamily Metaparasitince he says [10. 

 p. 235] »Der Name Metaparasitinse wurde gewählt, da diese 

 Gruppe fiir jiinger zu halten ist als die Parasitinae, deren 

 Männchen die Genitalöffnung vor dem Sternalschilde trägen; 

 diese Stellung der Genitalöffnung ist of f enbär eine primitivere.» 



Now it is possible that in the subfamilies, where the J* 

 genital aperture is placed at the front margin of the sternal 

 shield, a form may ha ve undergone a retrogressive develop- 

 ment in so far that the ^ genital aperture has moved slightly 

 backwards again, and consequently in that group the for- 

 ward position of the aperture is the most primitive one. 



But this does not affect the question as to whether the 

 anterior or the posterior position is the most primitive one. 



That question must he answered by a comparative mor- 

 phological study of the Parasitidse. 



Undoubtedly, as Berlese has pointcd out in his Mono- 

 graph [2. p. 96 — 100], the Parasitince are amongst the more 

 recent subfamilies; a proof of this are their complicated secon- 

 dary sexual characteristics, such as the calcar mandibuli and 

 the spurs on legs II, as well as the more or less complete 

 fusion of their shields. Michael's classical investigations into 

 Parasitus crassipes and Euryparasitus terribilis has thrown 

 some light on the function of the secondary sexual charac- 

 teristics. M. describes how the coition is effected [6. p. 308]: 

 »The adult male rushed up to the female, approaching her 

 from behind; on reaching her, he turned suddenly över on 

 his back and slipped underneath the female, seized one of 

 her hind legs with each of his enlarged legs of the second 

 pair, which was doubled back upon itself. The leg of the 

 female was clasped between the great apophysis on the se- 

 cond joint of the enlarged leg of the male, which curves 

 forward and upward, and the smaller one on the fourth joint, 

 which in this position of the leg curves backward and down- 

 ward; this arrangement brings the genital aperture of the 

 male immediately below the vulva of the female, which is 

 placed further back than the male organ.» Låter, Michael 

 completed his observations on another species, E. terribilis 

 [7. p. 264—265]: »My conclusions from all this was that, in 

 the present species at all events, the male semen is enclosed 



