OCR Text |
Show 1875.] NEW SPECIES O F E R I G O N E . 395 lens ; figure 2 d represents those of the present species, and 1 c those of E. persimilis ; these two figures are taken from a sketch of each in a similar position, under a high power, by Mr. Emerton. The caput has a central longitudinal row of tuberculiform denticulations, like those of E, persimilis, but of a smaller size. Mr. Emerton remarks upon the darker and peculiar colour of this Spider when compared with E. persimilis; but this character, as far as it has yet been ascertained, is no certain specific criterion in the Spiders of this group ; a long series of two well-known species (E. dentipalpis, Wid., and E. atra, Bl.), will furnish every variety of depth of colouring. In regard to the present species, other minor differences are observable on a careful comparison with E. persimilis and other, nearly allied, species. These differences will have to be carefully noted when the numerous Spiders of this group come to be monographed; but for the present purpose the differential characters detailed above and in P. Z. S. 1874, p. 429, will be found sufficient for specific determination. A n adult male was received from Mr. Emerton, by w h o m it was found at Troy, near Boston, Massachusetts, U. S. A.; and a comparison of it, lately made, with the example described P. Z. S. I. c. shows the identity of the two. The present description notices the difference from E. persimilis (Cambr.), while that in P. Z. S. I. c. differentiates it from E. longipalpis, Sund., and some other species. ERIGONE ORNATA, sp. n. (Plate XLVI. fig. 3.) Adult male, length 1-L line. This species is very closely allied to Erigone pictilis (p. 396), resembling it very nearly in the pattern on the abdomen; the darker portion of it, however, is more mottled and marked with pale yellow, and an uninterrupted oblique and slightly curved stripe traverses each side. It may also be at once recognized from E. pictilis by the absence of the occipital elevation ; the occiput being only a very little, and uniformly, gibbous, or rounded, and, when looked at from above the caput, is less compressed laterally near its lower margins. The cephalothorax is glossy, and of a deep yellow-brown colour; and the caput has a few erect hairs on its upper part, as well as some others, directed a little backwards, on the ocular area; the height of the clypeus is half that of the facial space. The eyes are of moderate size, and relatively not greatly different from each other; they are in the ordinary position; those of the hinder row are equidistant from each other, being separated by spaces equal to the diameter of one of the hind centrals, those of each lateral pair are obliquely placed and contiguous to each other, the fore lateral eye being larger than the hind lateral; those of the fore central pair are the smallest and darkest-coloured, near together, but not contiguous to each other, and each of them is separated from the fore lateral eye on its side by an interval equal to its diameter; the front row of eyes is much the shortest, and, looked at from above, straight. The legs are not very long, but tolerably strong; their relative |