14 



ARKIV FÖR ZOOLOGI. BAND 7. N:0 28. 



Berlesé in his earlier papers, did not pay any attention to 

 it. Novv, however, their weight as evidence begins to be 

 aknowledged, and Reuter [12. p. 27 — 28] even goes so far 

 as to endeavoiir to solve the problem of the number of opi- 

 sthosomatic segments with the assistance of the number of 

 hairs. The author himself has in this respect followed Oude- 

 MANS and, based on the number and position of the hairs, 

 proved that in some genera the metasternal shields are fused 

 with the sternal one, and that in the Uropodince the epi- 



Fig. 21. 



Fig. 22. 



22. 



Pergamasus Lapponicus Tgdh. (after Tkägårdh). 

 Fig. 21. Female, ventral view X 74. 

 Male sterniti-metasternal shield, fused with the ventral one X 148. 



gynial shield is not morphologically equivalent to that of 

 the other Paras itidce. 



Let US now briefly consider some of the different types 

 of sterniti-metasternal and epigynial shields which we meet 

 in the Paras itidce. 



In the female of Pergamasus lapponicus Tgdh. we notice 

 the following features (Fig. 21): On the sternal shield there 

 are 3 pairs of hairs; one at the anterior margin; the other 

 two at the lateral margins, on a level with the middle of 

 coxse II and III respectively. On the metasternal shields, 

 outside the middle, there is another hair ; and on the epi- 



