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Show 182 A.RACHNIDES. secret of the impenetrable emargination, and has the key to those which alone afford an entrance. When her offspring are able to provide for themsel.ves7 t~e~ leave th~ir ~ati ve dwelling, to establish elsewhere thexr md1v1dual hab1tattons, while the mother retut•ns to it and dies-it is thus her cradle and her tomb." DRAssus, Walck. The Drassi differ from Clotho in several characters. Their chelicerre are robust, projecting and dentated beneath; their jaws are ob. liquely truncated at the extremity, and the ligula forms an inferiorly truncated oval, or an elongated curvilineat· triangle; the eyes are nearer to the anterior margin of the thorax, and the line fot·med by the four posterior ones is longer than the anterior, or extends beyond it on the sides. There is but little difference in the proportionsof the fusi, and we do not observe between them the two pectiniform valves peculiar to Clotho. Finally, the fourth pair of legs, and then the first, arc manifestly longer than the others. The tibire and first joint of the tarsi are armed with spines. These Spidet·s live under stones, in the fissures of walls, and on leaves; they construct their cells with an extremely white silk. The cocoons of some are orbicular and flattened, and consist of two valves laid one on the other. M. Walckenacr distt'ibutes the Drassiinto 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 calls viridissimus, IIist. des Aran. fascic. IV, 9, and which alone composes his third division, weaves a fine, white, transparent web on the surface of a leaf; under this web it seeks for shelter. I have sometimes observed a similar web on the leaf of the Pear-tree, but the margin was angular and resembling a tent, like that of the Clotho, beneath which was the cocoon. It is, I presume, the work of this species of Drassus, and proves the analogy of this subgenus with the pre· ceding one. M. Leon Dufour, Ann. des Sc. Phys., VI, xcv, 1, has given a very complete description of a species of Dras· sus-D. segestriformis-found by him undeJ' stones in the highest Pyrennees, and never beneath the Alpine region. It is one of the largest of this subgenus, and appears to me to be closely allied to my melanogaster, which I believe to be the D. lucifugus of Walckenae1·, SchrefY. Icon. Cl, 7. One of the prettiest species, which is very commonly observed running along the ground in the vicinity of Pat'is, is the D. relucens. It is small, and almost cylindrical, with a fulvous PULMON A RilE. 183 thorax, invested with a purple silky down; the abdomen is a mixture of blue, red, and green, with metallic reflections, and'" marked by two transverse and goldeu lines, of which the anterior is arcuated. Four golden dots are sometimes observed on it( I). In the other Tubitelce the jaws do not surround the ligula; their external side is dilated inferiorly beneath the origin of the palpi. Some have hut six eyes, four of which are anterior, and form a tran&verse line, and the two others posterior, situated, one on each side, behind the two lateral ones of the preceding line. Such is the essential character of the SEGESTRIA, Lat. The ligula is elongated and almost square. The first pair of legs, and then the second, is the longest; the third is the shortest. These spiders construct long, silky, cylindrical tubes in the chinks and crevices of old walls, which they inhabit; their first pairs of legs are always directed forwards, and diverging threads border the external entrance of their domicil, forming a net for ensnaring Insects. The genital organ of the S. perjida-.!11;anea jlorentina, Ross., Faun. Etrusc., XIX, 3-a large black species with green chelicerce, which is not rare in France, is shaped like a tear, or is ovoido-conical, very a~ute at the end, entit·ely salient, and red(2). The remaining Tubitelre have eight eyes. On account of the difference in the site of their habitations, we may divide them into the terrestrial and the aquatic. Although the last family of the Araneides of Walckenaer (his Naiades) is composed of these latter, th~y a~e so .closely allied to the other Tubitelce, that notwithstanding th1~ d1spanty of habits they must be placed together. In those W~Jch are terrestrial, the ligula is almost square, or but very ~hghtly narrowed, with a very obtuse or truncated summit; the Jaws are straight, or neal']y so, and more or less dilated towards the extremity; the two eyes of each lateral extremity of the ocular grou_p are generally separated from each other, or at least are gemi~ate and placed on a particular eminence like those of the aquatic Tubitelre. CLUDIONA, Lat. This subgenus is only distinguished from the following one by ~~;!or the other species, see Faun. Paris., Walck., and Tabl. des Aran., Id. L . D dd the Seg. 8enoc1elata, Walck., Hist. des A ran., V, vii; .llraneasenoculata, ., eg. |