ON EUROPEAN SPIDERS. 151 
distinguished by generical names. (See Nouv. Dict. d'Hist. Nat., XXIV, p. 
133—136). These groups are: Æriodon, Dysdera, Segestria, Argyroneta, 
Gnaphosa, Clubiona, Tegenaria, Scytodes, Linyphia, Aranea, Heteropoda, 
Misumena, Micrommata, Oxyopes, Dolomedes, Lycosa and Salticus. Although 
he did. not himself immediately, but only some time afterwards ?), expressly 
call these groups "genres", it is beyond a doubt that they ought to be 
considered as genera formed by LATREILLE, and their names accordingly to 
have right of priority before subsequently proposed, synonymous denomina- 
tions. This is also usually admitted as regards most of them, those in fact 
which were retained by WALCKENAER in his Tableau des Aranéides (1805). 
As to the groups which received new names from WALCKENAER, LATREILLE 
in his subsequent works retained the appellations he had given to « part 
of them ( Eriodon, Micrommata, Oxyopes and Salticus), whence also some 
arachnologists have adopted these names, whereas others have made use 
of the corresponding Walckenaerian denominations; but the names Gnaphosa, 
Aranea, Heteropoda and Misumena LATREILLE himself in time abandoned, 
and adopted the corresponding Walckenaerian synonyms, whereby these 
names have gradually fallen into oblivion. In the mean time, as no rational 
cause can be assigned, why these names should not be retained, as well 
as those, whieh belong to the two first named categories, I have adopted 
all LATREILLES generic names, with the single exception of Aranea, Ara- 
nec being the general name for the entire order of spiders. 
* Gen. 13. THYSA Kemp. 
Deriv.: probably Ovow, a name of the female bacchanals (Iv, to rage). 
Syn.: 1867. Thysa Kemp., Thysa pythonissæformis, p. 607 (1). 
Type: Zhysa pythonissæformis KEMP. 
YI gsm py 
The remarkable spider, for which this genus has been formed, and 
of whieh only one specimen, a female, has been found (at Erlau in Hun- 
gary), is known to me only through KEMPELEN' description and figures (loc. 
cit.) According to him it is related to Pythonissa (Gnaphosa), but has 
only six eyes. If we imagine to ourselves a Gnaphosa without the anterior 
central eyes, and with the posterior row curved strongly backwards, we have 
much about the same position of the eyes as in Zhysa. But this animal 
LE] 
1) In his Cours d’Entomologie, p. 501, he says: ”... je perfectionnai ma distribu- 
tion et j'y établis la plupart. des genres admis aujourdhui. (Nouv. Dict. d Hist. Nat.).” 
