238 
AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
No. 90. Zilla atrica C. Koon. 
1802. Aranea calophylla, WALCKENAER . 
1805. petra calophylla, WALCKENAER . 
1834. Zygia calophylla, Koon, C. 
1844. Eucharia atrica, Kocu, C.. .. « 
. Herr.-Schaeff, Deutschl. Ins., 123, 17. 
Plate XVII, Figs. 7, 8. 
(In part.) 
(In part.) 
Faune Par., ii., p. 200. 
Tabl. d. Aran., p. 62. 
(In part.) 
Die Arachn., xii., p. 103, pl. 419, Figs. 1030, 1031. 
Es ae 
1851. Epeira atrica, WESTRING . Forteckning, ete., p. 35 
1856. Zilla atrica, THORELL . .... Recensio Critica, p. 107. 
1861. Zilla atrica, WestRING ..... Araneze Svecicie, p. 69. 
1864. Epeira calophylla, Buackwaun. . Sp. G. B. & I, ii, p. 338, xxv., 245. 
1866. Zygia atrica, Menace .....-. Preuss. Spinn., i, p. 78, pl. 12, tab. 20. 
1867. Zygia calophylla, Outre . . . . Aran. d. Proy. Preuss., p. 30. 
1889. Zilla atrica, McCook ...... Amer. Spiders and their Spinningwork. 
1889. Zilla atrica, Marx ....... Catalogue, p. 550. 
Femate: Total length, 8 mm.; abdomen, 5.5 mm. long, 3.5 mm. wide across the base ; 
cephalothorax, 4 mm. long, 2.5 mm. wide; the face, 1.5 mm. The general colors of the fore 
part are yellowish brown, and of the abdomen yellow, white, and blackish. 
Crrnatormorax: A long oval; black on the summit; the sides high; fosse a longitu- 
dinal slit; corselet grooves not distinct; cephalic suture distinct; color brownish yellow, 
lighter on top, with a patch blackish at the caput base, and a dark band passing thence to 
the eye space; slightly pubescent, especially around the caput base; skin glossy along lower c 
margin of corselet; a row of bristles curved along the front. Sternum longer than wide, 
shield shaped; glossy at the margin, with a broad yellow median band; sternal cones dis- 
tinct, indented on the edges, raised in the centre. Labium triangular; maxille as broad as 
long; subtriangular at tip; light brown, shading to yellow at tip. 
Eyes: Ocular quad slightly wider behind than in front, and the side somewhat longer. 
Eyes about equal in size. MF separated by about one diameter; MR by about 1.5 diameter. 
Side eyes on tubercles; contingent; about equal in size, and not greatly different in size 
from MR. SR removed from MR by a space but little greater than the distance between 
MR. The space between SR and MR at least twice the distance between the latter. The 
front eye row recurved; the rear row longer, and procuryed. The clypeus is about the 
height of one diameter MF. ; 
Leas: 1, 2, 4, 3; stout, particularly the femora; yellow, with dark brown annuli at tips 
of joints, and median annuli on femora and tibia, especially underneath; spines short, 
black, few in number; the joints not heavily but sufficiently clothed with yellow hair and 
bristles. Mandibles uniform’ brown, slightly pubescent, extending almost directly from the 
face, and sharply bent downward; conical; quite thick at the apex; parallel. 
Axspomen: Oval, but slightly diminishing toward the apex, where it is nearly as thick 
as at the base. The folium is a broad, oval figure, with undulating margins of black, 
mottled with yellow, there being about five prominent scallops thereto; it narrows to the 
apex; the central part is yellow, with branching longitudinal lines from the median point 
backward. The dorsum is reticulated, the sides well covered with hairs, the whole having 
a slightly glistening appearance in life. The venter has an irregular rectangular patch of 
brownish yellow, well covered with yellowish hairs, and a margin reticulated on either side. 
The epigynum (Fig. 7a) is dark brown, glossy in color, lacking the prominent scapus char- 
acteristic of most species of Epeira. The figure on the plate is n6ét a very good representa- 
tion thereof. 
Tue Mare: Figs. 8, 8a. Is smaller than the female, being 6 mm. long, and resembles 
it in general color and markings, although the legs are less decidedly annulated. These 
members are long, provided with comparatively few spines, with no special clasping spines 
upon tibia-II; color uniform yellowish brown. The palps (Fig. 8a) are long and strong, and 
thus are an admirable substitute for the tibial clasping spurs. 
Zilla atrica is distinguished from Z,. x-notata, which it strongly resembles, (1) by the 
reddish brown color of the mandibles; (2) it does not have, in the living species, the 
shining black, and, after death, the blackish, color of the latter; (3) the black bases of the 
