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Show 1896.] SPIOERS FROM THE LOWER AMAZONS. 763 tumulus low; anterior row of eyes a little procurved (posterior margin of laterals aligned with centre of medians) ; the latter circular, half a diameter apart, the same distance from laterals, their diameter distinctly less than axis of laterals. Laterals ellipsoidal, distinctly separate, anterior a trifle larger than posterior. Central posteriors very small, equidistant from central anterior and posterior laterals \ Sternum a trifle longer than broad ; four pairs of sigilla visible- 1st pair at base of labial plate ; 2nd, 3rd, and 4th small, marginal. Labium broader than long, not spinulose. Coxa of pedipalp \ longer than broad; anterior distal angle slightly produced and bluffly rounded, not spinulose; basal anterior angle and central basal disk studded with minute cuspules. Legs 4, 1, 2, 3. Femora clothed beneath with long silky hairs; other segments similarly, though less thickly. Tibiae, protarsi, and tarsi with a few spines beneath, especially iii. and iv. Spinners four. Posteriors as long as abdomen, trisegmental; two basal segments subequal, normal; terminal 1 m m . longer than both basals taken together, nexuose, caudiform, attenuate at apex; separate at base a distance equal to length of both basals taken together. Anterior spinners 2 m m . long, separate at base 5 longer than one of them. Tarsal claws three, superiors armed with 10-11 long denticles, inferior with four or five. Outer margin of fang-groove with 10 stout teeth, inner margin with 9 ; a third row of minute cusps close to outer row on inner side at base. Measurements in millimetres (largest specimen).- 2- Carap. 7 long., 5-5 lat. Abd. 11 long., 8-25 lat. Stern. 3 long., 2-n lat. Coxa of pedipalp 2 long., 1-5 lat. Pedes 4, 1, 2, 3 -iv. 13 long. Postr. mam. 11 long. Artl. 3-2-75-5*25 long., 4 separate. Antr. mam. 2 long., 2-5 separate. Mandibles 3 long. This species is, without any doubt, one of the most abundant spiders on the Lower Amazons. It abounds almost everywhere, forming its white, sheet-like web, constructed sometimes in tiers, one sheet, above the other, under the bark of trees, amongst foliage, in the hollow centres and amongst the spikes of pine-apple plants, and in the crevices and crannies of ruined buildings. Occasionally, too, they are constructed, like those of our Agelena, on the ground. In general character the Spiders bear a strong resemblance to this genus as well as to Textrix, and the speed of their rapid retreat reminds one very much of the latter Spider. The web, too, is very similar to that of Tegenaria or Textrix in character. Though so abundant, they are not easily secured on account of their rapidity, and I was unfortunate in not securing a single male. It occurred everywhere from I'ara to Manaos, along the river margin and in the forest on tbe " terra firma." Whether it extends far north or south I canuot say, though 1 should not be surprised to find it through the entire valley of the Amazons. The species forms an addition to the Museum collection. These characters must be used with great caution. |