THE EPEIRID/E 



189 



Fig. 438. Acro- 

 soma mitrata, 

 enlarged four 

 times. 



Acrosoma mitrata. — This is a smaller species than nigosa or 

 spinea. The abdomen does not extend as far backward as in 

 the other species, but comes farther forward so as to cover 

 half the cephalothorax (fig. 438). The abdomen 

 is truncated behind, with two pairs of pointed 

 processes at the corners, one pair below the other. 

 In front, the abdomen is a little narrowed over 

 the thorax. The legs and cephalothorax are 

 brown, as in the other species. The abdomen 

 is light yellow, darker behind, with two or three 

 pairs of black spots along the middle and five 

 or six dark elongated spots along the sides. 

 The under side is black mixed with yellow spots, as in the 

 other species. Common as far north as Connecticut. 



Acrosoma rugosa. — This has five pairs of spines on the abdo- 

 men, three pairs in the same places as those of spinea and the 

 other two pairs behind and under the last of the three. All 

 the humps and spines are about the same size. 

 The cephalothorax and legs resemble those of 

 spinea, but the legs are shorter. The colors are 

 white, yellow, and brown in spots and marks 

 like those of spinea, some individuals being 

 almost white, and others as nearly black. The 

 males have a long slender abdomen without 

 humps or spines. This is a common spider as 

 far north as Connecticut, where it is occasion- 

 ally found. 



Fig. 439. Acrosoma Acrosoma spinea. — This spider is distinguished 

 rugosa, enlarged fj-Qj-j-^ ^\ j;|-,g commou specics by the shape of 



four times. 



its abdomen, which is narrow in front and has 

 two long spreading points behind (fig. 440). There is a pair of 

 smaller spines on the front of the abdomen and another near 

 the middle of each side. The middle of the abdomen is white 



