Superfamily Argiopoidea 



Genus ANTHROBIA (An-thro'bi-a) 



The eyes are wanting and the pedipalps of the female have 

 no tarsal claws. Only a single species is known. 



Anthrobia mammouthia (A. mam-mouth'i-a). — The adult 

 measures six hundredths of an inch in length. It is pale 

 brownish yellow; the abdomen is almost white, with brown hairs; 

 the ends of the pedipalps and the epigynum are reddish brown. 



This spider was first described from the Mammoth Cave; but 

 it has since been found in other caves. Its eyeless condition is 

 an excellent illustration of the loss of an organ through disuse. 

 The species is doubtless descended from an eyed form, and has 

 lost its eyes as a result of living in the dark for many generations. 



Genus PHANETTA (Pha-net'ta) 



This genus like the preceding includes a single cave-inhabit- 

 ing species; but this is not blind. The eight eyes are present, 

 although the anterior median eyes are greatly reduced in size. 

 The pedipalps of the female have no tarsal claw; in this respect 

 this genus agrees with Anthrobia and Troglohyphantes and 

 differs from all other members of the Linyphiinae. It differs 

 from Troglohyphantes in having the posterior median eyes about 

 as close to the posterior lateral eyes as to each other, and in that 

 the anterior median eyes are barely the diameter of one of them 

 apart. 



Phanetta subterranea (P. sub-ter-ra'ne-a). — The length of 

 the body is about one twentieth of an inch. The cephalothorax 

 and legs are yellowish brown, in some specimens reddish; the 

 abdomen is white with brown hairs. 



This spider occurs in caves in Kentucky and probably in 

 caves elsewhere. 



Genus TMET1CUS (Tmet'i-cus) 



The clypeus is flat; the posterior eyes are moderately widely 

 separated; and the lateral eyes are not at all or but slightly 

 protuberant. 



These are small spiders which agree with the following genus 

 in having nearly square endites, and in that the tibiae are without 

 lateral spines; but differ in that the clypeus is flat, the posterior, 



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