ORDER PULMONARI^. 407 



robust, projecting, and denticulated underneath; their jaws 

 are truncated obliquely at their extremity, and the tongue 

 forms an oval, truncated inferiorly, or an elongated curvilinear 

 triangle ; the eyes are more approximated to the anterior 

 edge of the thorax, and the line formed by the four posterior 

 is longer than the anterior, or extends beyond it on the sides. 

 The proportions of the external spinnerets differ but little, 

 and we do not see, between them those two pectiniform 

 valves which are proper to the clothos, Finall}', the fourth 

 feet, and next the first two, are very manifestly longer than 

 the others. The legs, and the first articulation of the tarsi, 

 are armed with prickles. 



These arane'ides remain under stones, in the clefts of walls, 

 and the interior of leaves, and there fabricate cells of a very 

 white silk. The cocoons of some are orbicular, flatted, and com- 

 posed of two valves applied one upon the other. M. Walcke- 

 naer distributes the Drassi into three families, according to 

 the direction and approximation of the lines formed by the 

 eyes, and the greater or less dilatation of the middle of the 

 jaws. 



The species which he names viridissimus, (Hist, des Aran, 

 fasc. iv. 9.) and which alone composes his third division, 

 constructs on the surface of leaves a fine, white, and trans- 

 parent web, beneath which it establishes itself. One of the 

 sides of the leaves of the jjear-tree has sometimes presented 

 to my observation a similar web, but angular at the sides, in 

 the form of a tent, like that made by Clotho, and under which 

 was the cocoon. It is, I presume, the work of this species of 

 Drassus, and indicates the analogy of this subgenus with the 

 preceding. M. Leon Dufour has given us, in the Annals of 

 the Physical Sciences {Drassus segestriformis, VI. xcv. 1.) a 

 very complete description of a species of Drassus, which he 

 found under stones in the high mountains of the Pyrenees, 

 and never below the Alpine Zone. It is one of the largest 



