60 T. THORELL, 
in his work but one genus, Myctobia [Nuctobia] Sn, with Meta and 
Zilla as sub-genera. (On this subject see further under the article Meta). 
As type for the genus Zilla, Koc ?), it is true, gives Z. albimacula (Ep. 
diodia WALCK.), but as we feel ourselves obliged to refer that species to 
the genus Epeira, we have assumed as typical species Zygia calophylla 
(WaLckK. C. Koch = Z. «-notata (CLERCK), which appears to us best to 
express the peculiarities of the genus, is the first species of the genus de- 
scribed, and has since been by KocH himself assigned to Zilla, to- 
gether with the very closely related Zilla montana C. KocH. He accord- 
ingly himself combined in one the genera Zygia and Zilla, and entirely sup- 
pressed the former name. In Zilla we also include a part of the unnatural 
genus Æucharia C. Koco — which is formed chiefly of Theridioidæ and is 
synonymous with Steatoda (SUND.) NOB. — viz. E. atrica C. Koch. Kocu's 
Z. reticulata (Ar. seymentatus CLERCK.) we refer to Meta, his Z. albimacula and 
Z. acalypha to Epeira. The limits assigned by us to the genus are accord- 
ingly the same as those proposed by WESTRING (loe. cit.), which limitation 
has the right of priority before that adopted by SIMON and OHLERT. In 
SIMON, Zilla is a sub-genus under his Nyctobia, with about the same limits 
as in KocH, but includes also species?), which according to the characteri- 
stics given by Simon himself and derived from the position of the interme- 
diary eyes, ought to be referred to his sub-genus Meta. — We have already 
above in treating of Zpeira (p. 55, 56) expressed our opinion that the characters 
whereby OmnLERT distinguishes Zilla and Zygia from Meta are utterly in- 
sufficient. MENGE and OHLERT readopt the genus Zygia abandoned by Kocx: 
MENGE separates it from Zilla in consequence of some difference in the organs 
of generation in both sexes, OHLERT only in consequence of the greater 
length, in the males, of the 4" joint of the palpi How nearly related to 
each other the species are, that compose the genera Zygia and Zilla of 
these authors, is evidenced by the fact, that Zilla atrica and Z. &-notata 
(calophylla), which are so like one another as to be considered both by 
WALCKENAER and SUNDEVALL as one and the same species, and to have 
been confounded by OHLERT himself in his synonyms, are the former a Zygia 
Our. and the latter a Zilla OHL. The name Zygia was disposed of long 
before it was applied by Koch to denote a genus of spiders, and ae- 
cordingly cannot on any terms be retained?). Also OHLERT assigns Kocn’s 
1) Uebers. d. Arach.-Syst., loe. cit. 
2) Zilla inclinata and Z. antriada (WALCK.) Srw., which latter is synonymous 
with Meta Meriane C. Kocx, but by no means with Zilla montana ID. 
3) Zygia Fasr. [Coleopt.] 1775. 
