Mr. Blackwall's Descriptions of new Species of Spiders. 635 



21. Ifalchenaëra hicolor. Maris cephalo-thorace mandibulis maxillis labio 

 sterno pedibiis palpisque brunneis; abdomine nigricante; cephalo-thoracis 

 parte anteriori prominente obtiisa utiinque indentatâ. 



Length of the male ^^yth of an inch ; length of cephalo-thorax -^^ ; breadth 3^^ ; 

 breadth of abdomen 3^ ; length of an anterior leg xi ; length of a leg of 

 the third pair -^. 



Cephalo-thorax oval, convex alîove, glossy, prominent, bnt obtuse, in front, 

 with a slight indentation in the medial line of the posterior region, and 

 another immediately behind each lateral pair of eyes. Mandibles conical, 

 armed with teeth on the inner surface, and inclined towards the sternum, 

 which is broad and heart-shaped. These parts, with the maxillre, lip, 

 legs, and palpi, are brown, the lip being the darkest, and the legs the 

 lightest coloured. First and fourth pairs of legs, which are tlie longest, 

 equal in length, third pair the shortest. Third and fourth joints of the 

 palpi short, the latter being much the stronger ; fifth joint somewhat oval, 

 having a projection on the outer side ; it is convex and hairy externally, 

 concave within, comprising the palpal organs, which are highly developed, 

 complicated in structure, with a slender, corneous process at the superior 

 part, directed upwards, a bold prominence on the inner side, and a fine, 

 convoluted, filiform spine, enveloped in a delicate membrane, extending 

 from the upper part of the extremity ; their colour is red-brown. Abdo- 

 men oviform, thinly covered with hairs, convex above, projecting over the 

 base of the cephalo-thorax ; it is of a brownish black colour. Plates of 

 the spiracles pale yellow. 



Males of this species, with the palpal organs fully developed, were taken in 

 July 1836, on rails near Llanrwst. 



22. If'alchenaëra pana. Brunnea, abdomine saturatiore ; maris cephalo-tho- 

 race anticè parùm prominente utrinque indentato. 



Length of the female Tsth of an inch ; length of cephalo-thorax 3^0 ; breadth 

 -^ ; breadth of abdomen 4^ ; length of an anterior leg -^ -, length of a 

 leg of the third pair -^. 



Cephalo-thorax oval, glossy, very convex behind the eyes, depressed in the 



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