Supcrfamily Argiopoidea 



(Fig. 384) there is a hump half as large as the rest of the cephalo- 

 thorax; this hump contains large cavities, which open by holes 

 on either side, as large as the eyes. These holes are connected 

 by a deep crease, which extends around the front of the hump. 

 The anterior middle eyes are near together in the middle of the 

 head in front of the hump; the other eyes are in two groups at the 



Fig. 383. CEPHALOTHORAX OF 

 TRACHELOCAMPTUS ROSTRATUS 



Fig. 384. CEPHALOTHORAX OF 

 GEDOTHORAX MONT1FERUS 



extreme corners of the head. In the female the back of the head 

 is considerably elevated, and the posterior middle eyes are farther 

 apart than usual. The length of the body is one 

 twelfth inch. 



CEdothorax probatus (CE. pro-ba'tus). — This 

 is probably the most common member of 

 Erigoninae. It is a small species, measuring 

 one sixteenth inch or a little more in length; 

 and is not striking in appearance, both sexes 

 being of ordinary form. The cephalothorax is 

 yellowish brown; the legs, dull yellow; and the 

 abdomen gray with five or six pairs of obscure 

 yellowish markings. The colour varies, some 

 individuals being almost black and others very 

 pale. 



Erigone aututnnalis (E-rig'o-ne au-tum- 

 na'lis). — In the palpi of the males of the genus 

 Erigone the patella is very long and is armed at 

 the tip with a large apophysis (Fig. 385); the chelicene are armed 

 with teeth on the front side; and there are small teeth on the 

 margin of the cephalothorax. Fourteen species have been cata- 

 logued from the United States. E. aututnnalis is a tiny spider, 

 measuring only one twentieth of an inch in length. It can be 



Fig. 385. PALPI 

 in ERIGONE 

 ADTUMNALIS 



373 



