2 ARKIV FÖR ZOOLOGI. BAND 2. N:0 8. 



finished text and drawings to our paper we asked Mr. Simon 

 to tell US his opinion on the sexual differences in the Tai- 

 tarides, as the scantiness of our material did not allow us to 

 decide this question. He answered that animals with thick 

 flagellum are males, and besides he most kindly sent us for 

 description a splendid material, nearly förty specimens be- 

 longing to ten species. Consequently it was resolved to add 

 to our paper a systematic treatment of the species. In order 

 to work out this part as well as possible we applied ourselves 

 to Rev. O. Pickard-Cambridge, Dr. R. Gestro (Museo civico 

 in Genova), Professor E. L. Bouvier (Musée d'Histoire na- 

 turelie. Paris), Geh.-Rath Prof. Dr. K. Möbius and Prof. Dr. 

 Fr. Dahl (Naturhistorisches Museum in Berlin) ; the result 

 was that we received some other forms, among which the 

 types of the species established by Cambridge and Thorell, and 

 that we can now raise the whole number of known species 

 from five to sixteen, of which fifteen will be described below. 

 We beg all these gentlemen to accept our sincere thanks for 

 the aid; above all we have to thank Mr. E. Simon for his 

 extreme kindness. 



The merely systematic portion of this paper has been 

 worked out by one of us, H. J. Hansen. But in the general 

 part of the paper we have embodied the main-results of the 

 study of the whole material, so that the more general account 

 of the group is founded on our examination of Schizomus 

 Simonis together with some additions derived from the know- 

 ledge of the other species. 



II. On the History of the Tribe. 



The essential literature on Tartarides may be briefly 

 dealt with. 



In 1872 O. P. Cambridge published the paper: »On a new 

 Family and Genus and two new Species of Thelyphonidea >> 

 (Ann. and Mag. Nat. Hist., Ser. 4., vol. X., p. 409—413; Pl. 

 XXII.) ; he established the genus Nyctalops on two species 

 and proposed the name Tartarides for the group founded on 

 that genus. It may be mentioned that Cambridge himself 

 says on his N. tenuicaudata : »Possibly this may be the female 

 of the former species [N. crassicavdata]; I am, however, 



