46 REV. O. p. CAMBRIDGE ON NEW ARANEIDEA. [Feb. 5, 



backwards. They are similar to the cephalothorax in colour, and 

 their surface is slightly granulose. 



The colour of the maxillae and labium is similar to that of the 

 falces. 



The sternum (which is nearly round) is of a deeper hue than the 

 cephalothorax, convex and granulose. 



The abdomen is rather large, oval, but projects greatly over the 

 thorax ; the short, but distinct pedicle connecting it with the thorax 

 entering the abdomen about midway between the most elevated 

 point and the spinners. The upper surface is shining glabrous, fur- 

 nished with a very few bristly hairs, of a dull clay-yellow, marked 

 rather irregularly towards the sides and hinder part with dull 

 brownish ; the lower portion of the sides and hinder part are rather 

 darker and strongly rugulose, giving the upper surface very much 

 the appearance of a shell or carapace, whose edge is margined by 

 a row of round, small, dull yellowish, somewliat cicatricose spots, of 

 which there are also two others, more conspicuous or wide apart, in 

 a transverse line on the hinder part of the carapace. The spinners 

 are small, apparently of ordinary structure, and inconspicuous. The 

 underside is dark brown, and at the fore extremity is a rather large 

 and somewhat quadrate coriaceous red-brown area, at the posterior 

 edges of which, at the outer corners, are the ordinary spiracular 

 openings, though scarcely traceable. Just in front of the spinners, 

 beneath the abdomen, is a long well-marked transverse fissure, which 

 is doubtless the entrance to another spiracular organ. 



Many years ago (1864) I received a large spider from the Swan 

 River, and described and figured it, but until a day or two sine? have 

 never had occasion again to look at it. Examining it, however, now 

 closely, I found on the inner side of one of the folded legs, among 

 its numerous hairs, the very minute spider (thus till now wholly 

 overlooked) which forms tlie type of the present new genus and 

 species. 



EXPLANATION OP PLATE II. 

 Fig. 1. Pachylomerus oiatalensis, s^.n.,^ (p. 35). 



a, Spider of natural size ; b, profile, without legs &c. ; c, maxillse, 

 labium, and portion of sternum ; d, entrance to trap-door nest. 



2. Idiops colletti, sp. n., § (p. 37). 



a, Spider, natural size ; h, profile, without legs &c. ; c, eyes, from 

 above and behind ; d, maxillaj and labium ; e, entrance to nest ; 

 ./', ditto, with trap-door raised ; g, section of upper part of nest. 



3. Moggridgea abrah0ni,B^.n., 5 (p- 41). 



a, Spider, natural size ; b, profile, without legs &c. ; c, eyes, from 

 above and behind; (?, portion of bark of "KaiBrBoom" tree, with 

 nest, showing (1) upper hinged lid, (!') lower ditto, both slightly open. 



4. 5. Stegodyphus gregarius, sp. n., <S and 5 (P- ■42). 



a, (5 , enlarged ; 6, 2 , ditto ; c, profile of (^■, d, ditto of 5 > showing 

 long hairs at a-; c, natural length of (5; /, natural length of J; 

 g, eyes, from above and behind. 

 6. Chasmocephalon neglectum, sp. n. c? (p- 45). 



a. Spider, enlarged ; i, outline of cephalothorax and abdomen ; 

 c, profile of ditto ; d, eyes from in front ; c, maxill» and labium ; 

 /, hinder extremity of thorax, showing excavation and insertion of 

 abdominal pedicle ; g, natural length of spider ; h, cephalothorax, 

 showing form of hinder part of thorax. 



