6 



T. THORELL. DKSCRIPTIONS OF SI:VP:KAL KrK(^rKAN" AM) N"ORTH-AFRICAN SPIDERS. 



of oyes is said to be such as it appears wheii viewed dircctly from the front, that of 

 the posterior row as uhen viewed directly from above. As the word distance between 

 two eyes may possibly be taken in more senses than one, I have preferred to use the 

 word interval {intevvallum, s/ja^mm), which can only mean the shortest distance between 

 the peripheries of the eyes: I have also for the same reason in general compared the 

 lieight of the elypeus with the length of the area occupied by the central eyes, not 

 with their 'distance' from each other. — The legs are measured from the inaro-inofthe 

 cephalothorax to the end of the tarsus; the nieasures of the ditferent joints of the legs 

 and palpi are always given as seen from the upper side. — In indicating the differences 

 between nearly related species, I have endeavoured as much as possible to point out 

 (tbsolute characteristics and to avoid relative ones, wliich are of no use to a person ^\'ho 

 knows only one of the species compared. If we, for exainple, are told concerning two 

 closely allied species, that a pair of eyes in the one species are nearer together than 

 in the other, this is evidently a far less help than it would be to know that the dis- 

 tance of the eyes is in the one species e. g. fully as great as, and in the other so- 

 laething less than, the diameter of an eye. 



The descriptions are all from speeimens preserved in spirits. Of course the animal 

 has been left to dry on. the surface, before the colours depending on the hairy covering 

 have been described. The form of the genital organs has also always been given such 

 as it appears when the animal is dry, and after the liair, uhich often covers the viilva, 

 had been removed by gentle friction. This organ should never be described such as 

 it appears when the animal lies in a fluid, for it then often presents an appearance 

 quite different from its true foruL 



I. orbitelarij:. 



Fam. EPElROIDyE. ) 



Gen. EPEIRA. 



E. Zimmermanni Thor. cephalothorace piceo, antice rufescenti, sterno nigro, pe- 



dibus nigro-annulatis, area oculorum mediorum proclivi, rectangula; abdomine supra 



sub-fusco, serie raacularum testacearum antice in medio dorsi, humeris in tubercula duo 



magna obtusa elevatis; ventre tuberculis carenti, nigricanti, maculis duabus flavis; 



corpore vulva; secundum medium late et profunde impresso, scapo ejus longissimo, fere 



formi, ad maximam partem testaceo. — 9 (id- Long. plus 11 millim, 



Svn.: 1875. Epeira Zimmermanni Thor., Diagn. Arau. Europ. aliquot iiov-., in Tijdschr. v. Entom., 



Deel XVIII. 



Femina. — Cephalothorax b^/^ millim. longus, 4^', '^'''^ latus, latitudiuc froutis 2V4 inillim., tuberculis 

 oculorum prominentibus, lateribus partis thoracicae modice rotundatis, parte cephalica auteriora vcrsus parum 

 angustata, iu lateribus levissime rotundata, irapressionibus ceplialicis loiigis et profuudis, sulco vel 1'ovea media 



•) Of the sub-families iiito which the Epeiroidae have been divided, tiie sub-tam. Anetince Thor. ought to be 

 suppressed: Prof. Menge has latelv informed me that his description of .4/je<e5 cce/eiroM doubtless is founded 

 on a young specimen of an Epeira (probably E. soUers), which by some accident had lost its tarsal claws 

 and mamillae. 



