182 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



between the midfront and sidefront eyes as compared with the typical Epeira.^ To 

 this group might also be assigned E. forata, E. linteata, and E. juniperi, although their 

 abdomens are not distinctly triangular, and lack shoulder humps. 



The larger Angulata, whose descriptions follow, ^ may be regarded as among the more 

 typical Epeira. They all make the typical Epeiroid wheel shaped web, which is often very 

 large, and occupy, especially during the day, a leafy nest above and at one side of the 

 snare, which they command by a taut trapline attached to the hub thereof In some parts 

 of the United States the most common Orbweavers belong to this group. One at least, 

 E. angulata, is distributed throughout the entire country ; and two, E. diademata and 

 E. angulata, are common in Europe, the former, indeed, being the best known garden Orb- 

 weaver. 



No. 40. Epeira gemma McCook. Plate X, Fig. 6; PI. IX, Figs. ], 2. 



1888. Epeira gemma, McCook Proceed. Acad. Xat. Sci., Phila., p. 193. 



1889. Epeira gemma, Marx Catalogue, p. 545. 



1892. Epeira gemma, Keyserlinq . . . Spinn. Amerik., Epeir., p. 115, vi., 85. 



Female: Total length, 19 mm.; abdomen, 16.7 mm. long, 16 mm. wide; cephalothorax, 

 6.9 mm. long, 6 mm. in the middle, and 2.8 mm. wide. One large specimen in my posses- 

 sion measures over 20 mm. in length. General colors yellow, with brown or darkish 

 markings, and for the fore part yellow and brown. 



Cephalothorax : Cordate, the base indented ; corselet rounded at the edges, rather low, 

 the fosse a deep rounded pit; corselet grooves tolerably distinct; cephalic suture sufficiently 

 marked ; color yellowish brown, with a gray median band, which is chiefly marked out by 

 long gray bristles; gray hairs abundant over the surface, which is glossy. The caput is 

 depressed, flattish upon the top, subtriangular at the base, wide, squarish at the face, colored 

 as the cephalothorax, with yellowish longitudinal bands upon the sides. Sternum heart 

 shaped, pointed at the apex, about one-fourth longer than broad, raised in the middle ; 

 sternal cones before coxa-III, and more rounded ones before coxfe-I, II ; a decided cone 

 opposite the lip ; color ruddy brown, covered with golden yellow and long bristlelike hairs. 

 Labium subtriangular; maxilte gibbous, somewhat longer than wide; both these organs 

 brown, with yellow tips, and the maxillse with a few brownish spines and yellow bristles. 



Eyes: Ocular quad on a well rounded prominence, length not greater than width in 

 front, the front decidedly wider than rear; MF on separate tubercles, larger than ME, sep- 

 arated by at least 1.5 diameter; MR separated by not more than one diameter. Rear eyes 

 on tubercles, not contingent ; SF somewhat larger than SR ; SF removed from MF by about 

 1.3 their area, or at least twice or more their intervening space; SR from MR by 2.5 to 

 three times the area of the latter. The height of clypeus about 1.5 to 2 diameters MF, 

 with a row of strong yellowish bristles along the margin ; the space between the eyes is 

 also sparingly marked with shorter bristles; front row slightly recurved, rear row slightly 

 procurved. 



Legs; 1, 2, 4, 3, as follows: 23 (24.2), 22.5 (23.2), 21.5 (21.6), 14.75 (15,5) mm. Stout, 

 thickly covered on all sides with long yellowish bristles and yellow spines, which are 

 numerous along the metatarsus and tibia; these are particularly abundant underneath 

 femora-II ; color yellow, strongly annulated with brown at tips of joints and along femora 

 underneath. Palps colored and armed as legs; mandibles strong, conical, brown, glossy, 

 with yellowish tips and yellowish white bristles upon the inner sides. 



Abdomen : Triangular ovate, slightly longer than wide, highly arched on the dorsum 

 from the cephalothorax, which it overhangs, to the distal spinnerets; basal front subtri- 

 angular, high, marked at the summit by two large conical humps; color blackish brown, 



' I venture to propose for this group tlie subgeneric name " Burgessia," in honor of the late Mr. 

 Edward Burgess, of Boston, the editor of Professor Hentz's " Spiders of the United States," who was favor- 

 ably known as an entomologist, and later was an eminent designer of sailing yachts. 



= Epeira gemma, angulata, diademata, Nordmanni, cavatica, Silvatica. 



