536 PROCEEDINGS OF THE ACADEMY OF [AugUSt, 



Key to the Herein Described Genera of Lycosidce. 



^. — Third eye-row nearly on a line with the second. 



I. — Lateral eyes of the first row about equidistant from the 

 second row and the anterior edge of the cephalothorax, 



Ocyale. 



II- — Lateral eyes of the first row at least twice as far from the 



anterior edge of the cephalothorax as from the second 



row, Dolomedes. 



B. — Third eye-row not nearly on a line with the second. 



I. — Superior spinnerets not longer than the inferior, dorsal eye 

 area usually considerably less than one-quarter the 

 length of the cephalothorax, legs usually well clothed 

 with hair, chelicera usually fully IJ times the length of 



the head in front, . . . Lycosa. 



II. — Superior spinnerets slightly longer than the inferior, dor- 

 sal eye area fully or nearly one-quarter the length of 

 the cephalothorax, legs slender with long spines and 

 few hairs, chelicera not longer than IJ times the height 



of the head in front, " . . Pardosa. 



III. — Superior spinnerets at least 1^ times as long as the inferior, 

 dorsal eye area less than one-quarter the length of the 

 cephalothorax, legs well clothed with hairs, chelicera 

 comparatively small, Pirata. 



Genus LYCOSA Latr. 



Following Simon, I have included in Lycosa, and not granted 

 separate rank, the genera Trochosa Koch, Arctosa Koch and 

 Tarentula Ohl. and Tlior. In the species here described it is im- 

 practicable to distinguish these genera, the interrelation of them is 

 so close and intermediate forms so difiicult to classify. When 

 genera become more difiicult to distinguish than the species which 

 compose them, it is clearest to adopt one comprehensive genus for 

 all. The following key will aid in distinguishing the species here 

 described : 



^.—Cephalothorax not more than 2.5 mm. in length, without a 

 distinct median light band. 

 I. — Sternum nearly twice as long as broad, .... nigra. 



II. — Sternum nearly round, suhlata. 



B. — Cephalothorax 2.7-4.6 mm. in length, with a distinct median 

 light band. 

 I. — Sides of cephalothorax brownish or yellowish, sterniun not 

 darker than legs. 



