430 ON SOME RARE ARACHNIDS 



figure in British literature of that organ. P. latitans (L, 

 Koch) is rather smaller than P. Latreillii (C. L. K.) or P. 

 Petive7-n (Scop.). It is of a deep uniform black, except the 

 tarsi which are yellow. The central posterior eyes are much 

 less than one diameter apart, whereas they are separated in' 

 the aforesaid spiders by a space much greater than the 

 diameter of one of them. The palpi are very characteristic, 

 and the males of this species can easily be distinguished from 

 their congeners by the curved spine which, rising at the base 

 of the palpal organs, runs round their external border and 

 terminates near the apex at the inner side. The tarsi and 

 palpal organs are bulkier than in the other species, and the 

 tibial apophysis is rather different in shape from that of P. 

 Petiverii (Scop.), which it most resembles in that respect. We 

 did not get adult females, but the vulva is well figured by 

 F. O. Pickard-Cambridge*. 



P. latitans had previously occurred in Dorset alone as far 

 as Britain is concerned. Chyzer and Kulczynski maintainf 

 that P. latita?is (L. Koch) is identical with P. prcefica (L. 

 Koch), and that the latter name has priority. P. latitans 

 (L, Koch) has occurred in France, Switzerland, Germany, and 

 Hungary. 



Prosthesima Petiverii (Scop.-Camb.). This is a common 

 English spider. I sent a few specimens to Professor 

 Kulczynski for his opinion. He states that they are 

 identical with the P. apricornm (L. Koch) as figured in 

 " Araneae Hungariae." He now believes however that 

 apricornm is only a variety of P. siibterranea (C. L. 

 Koch), which is synonymous with our P. Petive?-ii 

 (Scop.). 



Prosthesima pedestris (C. L. Koch). Both sexes at 

 West Wickham. Also a pair in cop. under a stone at 

 Swanage on June gth. 



* Handbook to the Study of British Spiders, pi. iv., fig-. 6. 

 t Araneas Hungarise, Tome II., part ii., p. 202. 



