Superfamily Argiopoidea 



AA. Femora of the legs almost entirely devoid of spines beneath. 



B. Abdomen triangular-oval, broad anteriorly. 



C. Epigynum short, not much longer than its width at the 



base. P. 500. N. vulgaris 



CC. Epigynum elongate. P. 498. N. benjamina 



BB. Abdomen uniformly oval. 



C. Dorsal surface of the abdomen with a dark band in the 



middle bordered on each side with a yellow stripe 



or a series of yellow spots. P. 502. N. pratensis 



CC. Dorsal surface of the abdomen with a yellow band in 



the middle or a series of yellow spots. P. 497. 



N. arabesca 

 The male of N. volucripes is unknown to me; the males of our 

 other species can be separated by the following table: 

 A. Coxa of the fourth leg with a coniform spur beneath. 

 B. Abdomen with a brown median band. P. 502. 



N. pratensis 

 BB. Abdomen with a yellow median band. P. 502. 



N. oaxacensis 

 AA. Coxa of the fourth leg without a coniform spur beneath. 

 B. Tibia of the second leg straight or nearly so. P. 498. 



hi. benjamina 



BB. Tibia of the second leg strongly curved, concave on the 



inner side. P. 497. N. arabesca 



Neoscona arabesca (N. ar-a-bes'ca). — This and the following 

 species are the two most common and most widely distributed 

 members of the genus in the United States occurring throughout 

 this country and far south of our border. This is the smaller of 

 the two species, rarely exceeding one third inch in length. It 

 varies greatly in size, mature individuals occurring that are not 

 more than half as long as others. It is distinguished from the 

 following species by its smaller size, the more nearly oval abdomen, 

 and the form of the epigynum (Fig. 527), which is comparatively 

 short. It varies greatly in colour and markings. The most com- 

 mon colour is a mottled brown or brown and red with white or 

 light yellow markings. What may be considered the typical mark- 

 ings is indicated in t he generic description above. The basal 

 triangular light patch is often divided into a pair of oblique spots, 

 with more or less distinct dark or red margins, and the narrow 



497 



