257 

 ZILLA ATRICA. 



Buoharia atbioa, C. L. Koeh., Die Arachn., Bd. xii., p. 103, 



tab. 419, fig. 1030, 1031. 

 Epeira oalofhylla, Blackw., 8pid. Great Brit, and Irel, p. 338, 



pi. xxv., fig. 245. 

 Zilla oalophylla, C. L. Koch., I.e., p. 148, tab. 216, fig. 538, 

 539. 

 The length of the male varies from 2 to 2 J lines ; and of the 

 female from 3 to 4 lines. 



This spider is very closely allied to Zilla X-notata ; some 

 examples of the female being often very difficult to distinguish 

 from females of that species. There are, however, differences of 

 coloration by which the two species may generally be dis- 

 tinguished, while the males are so strikingly dissimilar in the 

 form and structure of the palpi that they may bo separated at a 

 glance. 



The general appearanco and distribution of colours (or pattern) 

 is as nearly as possible like that of Zilla X-notata, Clerck, but Zilla 

 atrica is usually of a brighter yellow hue on the sides of tho 

 abdomon, which are also commonly more or less strongly tinged 

 with red. The two black patches also (one on each side of the 

 fore extremity of the leaf-shaped marking of the abdomen) are in 

 Zilla atrica generally of a deep red-brown colour. The palpi of the 

 male, instead of being short, as in Zilla X-notata, are very long ; 

 the cubital joint is rather long, bent downwards, and of a clavate 

 form ; the radial joint is inordinately long, at least double the 

 length of the cubital, slightly bent or curved, and has a very 

 small notched prominence at its extremity on the outer side ; it 

 is also furnished with numerous erect bristly hairs on all sides. 

 The digital joint is rather small, of a regular, but short, oval 

 form, and about half the length of the radial joint. The palpal 

 organs are moderately prominent and complex, with a 6trong 

 bifid process projecting outwards from their base, and a curved 

 black Bpine at their extremity. 



