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Arctosa cinerea (FabrJ.C. Koch from the shores of the Baltic, 

 and .4. halodroma (Walck.), C. Koch from the banks of the rivers 

 of central Europe, are certainly, as far as I can see, one and the 

 same species: I have had occasion to compare a pretty large number 

 of specimens, males as well as females, of both forms, partly from 

 Travemiinde, Gotland and Gotska Sandon, partly from Bavaria and 

 Silesia. From the latter, or "A. halodroma" (for specimens of which 

 I am indebted to the kindness of L. Koch and Zimmermann), the for- 

 mer, or "A. cinerea", differs only by its somewhat longer legs and 

 its rather paler colour : the rings on the legs, especially on the thighs 

 of d 71 , are in this form sometimes reduced to mere spots on the 

 upper side of the joint. "A. cinerea" seems also to be on an average 

 a little smaller than "A. halodroma", of which I have a female, the 

 cephalothorax of which is 8'/ 2 millim. long, whereas in the females 

 of "A. cinerea" in my collection the cephalothorax is only 6'/ 2 mil- 

 lim. long. Nevertheless in both forms the size varies considerably: 

 in both the body is sometimes darker and sometimes paler, with the 

 marking on the abdomen more or less sharply defined, often almost 

 obliterated. The differences between "A. cinerea" and "A. halodroma" 

 seem to me scarcely so considerable or so constant as to justify 

 the classing of the form halodroma as a separate variety of Troclu 

 cinerea. Grude ') has found this species in Livonia as well on the 

 sandy beaches of the Baltic , as on the banks of the Diina and other 

 rivers; I have also seen a specimen precisely similar to those from 

 the coast of the Baltic, which was found by Dr v. Porath far in- 

 land, on the beach of the lake Vettern, near Jonkoping, in the very 

 heart of Sweden. 



In my male specimens of Tr. cinerea, the cephalothorax is5'/ 2 

 — 1% millim. long; it is low, with the sides rapidly rounded and 

 the back almost straight. The 4 th pair of legs in d* is 3 2 / 3 — 

 3 6 / 6 , in ? 3'/ 5 — 3 2 / 3 times as long as the cephalothorax; the ti- 

 bia + patella of that pair is in cf 3 / i — 1 millim., in ? a little (not 

 more than */ s millim.) longer than the cephalothorax; the greatest 

 breadth of the cephalothorax exceeds the length of the tibiae of the 

 4 th pair by '/ 2 — 1 millim. in cT, and about i millim. in ?. The 

 mandibles are in both sexes considerably shorter than the metatarsi 

 of the first pair; the sternum is always black, having often a small 

 pale line in the middle. The tibial joint of the palpi in c? is double 



l) Verzeichn. d. Arachn. Liv-, Kur- u. Ehstlands, p. 449 (35). 



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