TRÄGÅRDH, MORPHOLOGY AND PHYLOGENY OF PARASITID.E. 17 



as for example many Uropodince; and an investigation into 

 these shows, that in reality this shield has no hairs. 



In the female of Urodinychus Kramerii Berl. (Fig. 26), 

 for instance, the epigynial shield, although very large, has no 

 hairs; round it we notice the same 5 pairs of hairs generally 

 found in the Parasitinoe. 



A comparison between the shield of U. Kramerii and that 

 of a species which has hairs, e. g. Pergamasus lapfonicus 

 Tgdh, shows that in the latter it is contiguous to coxse IV 

 and excavated at the margin to fit round these. In U. Kra- 



.^o 



Fig. 26. 



Fig. 



Fig. 26. Urodinychns Kramerii Berl. $, ventral view X 53 (after TrägIrdh). 

 Fig. 27. Parasitus fucorum DG. nympha, ventral side X 42 (after TrägArdh). 



merii, on the other hand, this is not the case ; but the shield 

 is separated from the coxse, by a narrow band connecting 

 the sterniti-metasternal shield with the ventri-anal one (Fig. 26). 



From this comparison it is evident, that the hair on the 

 genital shield, when it is present, is a secondary feature, de- 

 pending on the genital shield being fused with some other 

 shields or parts of the ventral shield. 



In the male of the Urofodince there are no less than 9 

 pairs of hairs. 



In the Rhodacarince, where in both sexes the sternal and 

 metasternal shields are fused into one, extending in the male 

 to the hind margin of coxse IV, in the female to the middle 



Arhii; för zooloyl. Bd 7. N:o 28. 2 



