HANSEN: ON SIX SPECIES OK KOENENIA. 213 



ture in the female (the figure terminates behind at the beginning 

 of the fourth segment); fig. i b exhibits — with the same degree 

 of enlargement — the same surroundings in the male (the figure 

 embraces besides the major part of the fourth segment with its 

 ventral pouch (p) and the hairs and setae on the left side). A 

 comparison between these two figures shows the very pronounced 

 difterence between the two sexes. The lobe from the third seg- 

 ment is distally considerably thicker in the male than in the 

 female and adorned with double the number of longer hairs; in 

 the female the two usual terminal processes are slender and close 

 to each other, while in the male the lobe is deeply divided into 

 two rather distant thick processes. The lobe from the second 

 segment is proximally much thicker in the male than in the 

 female; the distal part of the lobe is formed almost similarly in 

 both sexes, but with fewer and much longer hairs; the front wall 

 of the lobe presents as usual no protuberances in the female, 

 but in the male we find in front of and above the distal part of 

 the lobe five pairs of slender subcylindrical processes and two 

 pairs of big, distally rounded processes, each of all seven pairs 

 terminating in a stiff" seta; and all these fourteen processes form 

 almost a bundle which on the sides and especially in front sur- 

 rounds the distal part of the lobe. The difference in the genital 

 lobes between the two sexes of K. Whceleri is thus a very 

 great one, and it is to be expected that a rather similar or 

 perhaps another curious structure exists in the males of the other 

 species. And it must be mentioned that I have discovered no 

 other external diff'erence between the two sexes, either in the 

 body, in the legs, in the number and arrangement of hairs or in 

 the dimensions — and only one organ of the male, the flagel- 

 lum, is unknown to me. 



In our present state of knowledge I have found it impos- 

 sible to discover an explanation of the fact, that the collectors 

 — with exception of Prof. Wheeler — have captured only fema- 

 les (and immature specimens), and it is, indeed, very surprising 

 that Dr. Silvestri, Mr. Borner and I, who in all have captured 

 between 150 and 200 specimens of A', mirabilis, have not met 

 with one single male! Whether Prof. Grassi really has seen any 

 male specimen has now become doubtful to me. 



