DESCRIPTION OF GENERA AND SPECIES. 217 



corselet. The corselet is oval, somewhat longer than wide. It is ordinarily closely furred 

 with metallic white hairs, that give it a silvery appearance. The sternum is somewhat 

 longer than wide, and is often marked with prominent sternal cones. The lahium and 

 maxilla; are substantially as in Epeira, though the latter are rather longer than wide. The 

 eyes are divided into three groups, usually placed upon decided eminences. The eye rows 

 are both procurved, the anterior row slightly, the posterior row decidedly. The legs are 

 in order of length 1, 2, 4, 3 ; sufficiently stout, armored with hair, bristles, and spines, the 

 two terminating joints being usually attenuated in size, and the metatarsal joint of greater 

 relative length. The abdomen is commonly longer than wide, cylindrical or subcylindri- 

 cal, or a lengthened oval ; in some species the dorsal base is marked by shoulder humps, 

 in others the posterior margin and sides by tubercles. The colors are brilliant, sometimes 

 metallic. The skin is soft and thickly covered with hairs. Some of the largest species of 

 both American and exotic spider fauna are found within this genus. The males usually 

 differ much from the females, and are relatively small. The orbicular snare is frequently 

 decorated with ribbons of white silk, symmetrically arranged. 



No. 7 1 . Argiope cophinaria (Walckenaer). Plate XV, Figs. 1-6 ; PI. XVI, Figs. 5, 6; 



PL XVI, Figs. 1, 2. 



1837. Epeira cophinaria, Walcken.\ek . Ins. Apt., ii., 109; Abbot's Ga. S., No. 151. 



1837. Epeira ambitoria, Walckexaer . Ins. Apt., ii., p. 112. 



1839. Nephila vestila, Koch Die Arachniden, v., p. 35, pi. 153, Fig. 358. 



1847. Ejjeira riparia, Hentz J. B. S., v., 468 ; Sp. U. S., p. 106, xii., 5. 



1882. Argiope riparia, McCook .... Proceed. Acad. Nat. Sci., Phila., p. 256. 



1884. Argiope riparia, Emerton . . . . N. E. Ep., p. 329. 



1888. Argiope cophinaria, McCooK . . . Proceed. Acad. Nat. Sci., Phila., p. 1 ; and Amer. 



Spiders and their Spinningwork throughout. 



1889. Argiope cophinaria, ^Iarx .... Catalogue Described Aranefe, p. 541. 



Female: Total length, 20 to 28 mm.; cephalothorax, 11 mm. long, 8 mm. wide; 

 abdomen, IS mm. long, 11 mm. wide. The size of the adult female varies greatly, but the 

 above measurement gives one of the largest, although at times a gravid female is found 

 with even a much larger abdomen. 



Cephalothorax : A long oval, thin, flat on top ; fosse a deep rounded pit in the centre 

 thereof; corselet covered uniformly with grayish or silvery white hairs. A lighter band of 

 yellowish hue girdles the margin; the caput is low at the base, flat on top, tlie skin 

 beneath, like that of the corselet, yellowish brown, mottled with yellow, but so thickly 

 covered with silvery white hair as to disguise the color thereof. These hairs extend to the 

 eyes, and entirely encompass the forehead surrounding the upper part of the eyes. Sternum 

 shield shape, much wider at the base, and pointed at the apex; strong sternal cones, a 

 particularly large one at the apex ; flattened in the middle ; color dark brown to blackish, 

 with a broad bright yellow median band the entire length ; covered, particularly at the 

 margins, with white pubescence, intermingled with long, dark, spinous bristles. Labium 

 subtriangular, less than half the height of the maxillw, ^\liich are gilibous, somewhat 

 longer than wide, brown, with yellowish tips, and provided with strong, black, curved 

 bristles. 



Eyes : Ocular quad on a squarish elevation, which much projects in front, the rear eyes 

 at the base thereof; length much greater than width, the front narrower than rear; eyes 

 not greatly different in size, but MF are somewhat larger, situated on triangular projections 

 from the corner of the quad; separated by about 2.5 diameter; MR separated by 1.5 to 2. 

 Side eyes on strong black tubercles, separated by about one diameter of SR, which is 

 slightly larger than SF ; the space between SF and MF is about 1.3 the area of the latter, 

 or not more than 1.5 the separating space; the distance between SR and MR is 1.3 to 1.5 

 times greater than that which separates SF and MF ; the clypeus is rather high, the margin 



