Mr. Blackwall's Descriptions of new Species of Spiders. 655 



from its extremity ; one situated in front, and the other, which is the 

 smaller, on the inner side ; fifth joint oval, convex and hairy externally, 

 concave within, comprising the palpal organs ; they are moderately deve- 

 loped, complicated in structure, with a curved process at the upper part, 

 directed outwards, and a small, black, pointed, curved spine at the ex- 

 tremity; their colour is red-brown. Abdomen oviform, convex above, 

 projecting over the base of the cephalo-thorax ; it is thinly covered 

 with hairs, glossy and very dark brown. Plates of the spiracles dull 

 yellow. 



The spider described above was found under a stone in a moist pasture at 

 Oakland, in May 1838. 



Genus Linyphia, Latr. 



41. Linyphia cauta. Cephalo-thorace flavescenti-brunneo, marglnibus lineaque 

 medians, antic^ dilatata nigris ; mandibulis maxillisque brunneis ; labio 

 sternoque nigricantibus ; pedibus palpisque flavescenti-brunneis nigro- 

 fasciatis ; pedum pari Imo longissimo, dein 2do, 3tio brevissimo ; abdo- 

 mine flavescenti-brunneo albo-punctato, antic^ nigricanti-guttato postice 

 transversim lineato, lateribus nigricantibus fascia longitudinali mediana 

 flavescenti-brunneS. albo-maculata, maculis tribus confluentibus flavis 

 rhomboidem efFormantibus ad basin filatoriorum inferiorum. 



Length of the female -^ths of an inch ; length of cephalo-thorax ■^; breadth 

 ■Yis ; breadth of abdomen yjj ; length of an anterior leg -^ ; length of a 

 leg of the third pair \. 



The anterior part of the cephalo-thorax, on which are distributed some long 

 hairs directed forwards, is compressed ; and in the medial line of the 

 posterior region there is a large indentation ; it is of a yellowish brown 

 colour, with black margins, and a band of the same hue extending along 

 the middle, whose anterior extremity is greatly enlarged. The eyes, 

 which are seated on black spots, are arranged in two transverse rows on 

 the fore part of the cephalo-thorax ; the intermediate ones form a trape- 

 zoid, whose anterior side is the shortest ; the other four are disposed in 

 pairs on the sides of the trapezoid, the eyes constituting each pair being 

 placed obliquely on an eminence, and almost contiguous ; the posterior 



