28 T. THORELL, 
with 6, and Binoculine with 2 eyes I). Now not only is a fourth tribe 
wanting for the spiders, which have no eyes, as e. g. Stalita SCHIÖDTE and 
Hadites KEYSERL., of which genera the first is nearly connected with 
Dysdera and the other is, so to say, a blind Agalena; but this whole sy- 
stem of classification lies open to the objection, that it is entirely artificial. 
By a one-sided adherence to a single feature not correlated with an aggre- 
gate of characters or intimately affecting the whole organism of the animal, 
nearly related forms are, as is well known, almost always widely sundered, 
and others, which are really far removed from one another, united in the 
same division, — and this is also the case when spiders are grouped ac- 
cording to the number of their eyes. As proof of this assertion we need 
no more than to refer to the genera Pholcus and Spermophora (Rachus), 
of which the former has 8, and the latter 6 eyes. One species of the last 
named genus was first described by DUGES ?) under the name of Pholcus 
senoculatus, and is in fact so like a Pholcus, that WALCKENAER doubted the 
correctness of Ducks’ statement as to the number of the animals eyes, nor 
was it until Lucas ?) also had found a six-eyed Pholcus, (Ph. 4-punctatus 
Luc., no doubt identical with the Pholcus senoculatus), and thus confirmed 
Ducs report, that WALCKENAER formed for these animals the genus Ra- 
chus *). The North American Spermophora ( Oophora) meridionalis described 
by Hentz ?) is said also to differ from Pholcus only in having 6 eyes and 
1) WALCKENAER also has made use of the number of eyes as a basis of classifi- 
cation: he however first separated "les Théraphoses” (Mygalidæ) from other spiders 
("les Araignées"), and then divided (as early as 1833) these others into two divisions, 
spiders with 6 and spiders with 8 eyes (Mém. sur une nouv. classif. d. Aran., p. 438). 
When he afterwards became acquainted with the 2-eyed genus Mops Mac LEAY, a 
third division was added for its accommodation, so that in WALCKENAER’S Ins. Apt., 
I, p. 510, 511 (1841) we find "les araignées” divided into "Jes Binoculées, les Sé- 
noculées" and "les Octoculées.” — Whether any 4-eyed spiders exist, is uncertain: the 
Tessarops maritima RAFIN., which is said to be distinguished by that unusual num- 
ber of eyes, is so ill described and drawn, that one cannot feel certain even that 
this animal is a spider at all. (Conf. RAFINESQUE, Descript. d'une araignée qui con- 
stitue un nouv. genre, p. 88, Pl. 116, fig. 1). 
2) Observations sur les Aranéides p. 160; — Cuv., Règne Anim., Arachnides, 
Atlas, Pl. 9, fig. 7. 
3) Exploration de l'Algérie, Arachnides, p. 239, Pl. 15, fig. 2. 
4) Hist. Nat. d. Ins. Apt., IV, p. 459. 
5) Deser. and fig. of the Aran. of the United States, in Boston Journ. of Nat., 
VI, p. 286. 
