Sex Ratio of an Arauead 435 



Adult female. Maximum dimensions: abdomen from anterior 

 convexity to spinnerets, 12 mm.; first leg, 21 mm., second leg, 15 

 mm.; third leg, 13 mm.; fourth leg, 20 mm. Rufous black is the 

 color of the cephalothorax, sternum and legs, and only the meta- 

 tarsi and tarsi are lighter. The abdomen is deep black, enormous, 

 nearly globular and arched on all surfaces except the ventral; it is 

 marked only by a broad red mark on the venter behind the epi- 

 gynum, a short red median band just dorsal to the spinnerets, 

 and (rarely) traces of other red spots along the dorsum; at the 

 dorso-anterior border are one or two narrow transverse red marks. 

 In a few specimens from more northern localities the dorsal red 

 spots were prominent, and in one only a pair of oblique red bands 

 on each side. The female is thus shining black with a few red 

 markings. 



Fig. I 



Adult ?nale. As shown by the accompanying figure the male is 

 much smaller than the female, with elongate abdomen; in this 

 figure the abdomina are shown from ventral and lateral views and 

 the stippled areas denote the light markings; he has also propor- 

 tionately longer and more slender legs. The cephalothorax and 

 sternum are both pale brown with darker borders, the cephalo- 

 thorax also with a darker median stripe. The legs are yellow; 

 the distal ends of the femora and patellae are darker, and there are 

 two rings of the same dark color at the distal ends of the tibiae. 

 The abdomen in seven specimens has a broad white dorso-median 



