chamberlin: the arachnida. 



289 



A species in several respects much like a Pardosa rather than a 

 Lycosa. The palpal organ of the male has the structure typical of a 

 Lycosa. 



Arctosa altamontis, sp. nov. 

 Plate 23, fig. 7-9. 



Carapace with the usual wide median pale spot back of the eyes 

 with radiating lines down the sides, this area abruptly narrowed at 

 caudal end of thoracic groove and running as a much narrower tongue 

 down the posterior declivity; on each side above the black margin a 

 series of large, in part confluent light spots, the row bending up to 

 the third eye on each side. Eye-area black excepting for short tongue 

 of light color between the third eyes. The light areas clothed with 

 grey hair. Sternum black. Labium black except distally. Endites 

 testaceous. Chelicerae brown or light testaceous. Legs yellow, 

 closely annulate with black, the annuli commonly incomplete below 

 and often broken into spots ; femora with four dark rings of which the 

 most distal is proximad of the end; papilla with one ring at proximal 

 end; tibia with two rings and metatarsus with three. Abdomen with 

 venter and lower part of sides clear greyish yellow; a dusky band over 

 each anterolateral corner broken into irregular spots farther caudad; 

 at base with a median longitudinal lanceolate mark of brown with two 

 small triangular black marks on the edge of each side; basal mark 

 followed behind by a series of pairs of dark, often indistinct, marks 

 which may in part be confluent. 



Cephalothorax low. Head rather broad with sides of face sloping 

 outward as usual; the eyes removed from lateral edges of the head. 



Anterior row of eyes clearly shorter than the second (38:45); a 

 little procurved; median eyes decidedly larger than the laterals (ratio 

 of diameters as 10:7), three fifths their diameter apart, not fully a 

 third as far from the laterals. Clypeus narrower than the anterior 

 median eyes (about three fifths as wide) . Eyes of the second row one 

 and three fifths the diameter of an anterior median eye ; their diameter 

 or very nearly so, apart. Third eyes each slightly smaller than the 

 second (about as 15:16 in diameters), just twice their diameter apart. 

 Quadrangle of posterior eyes much wider behind than in front (57:45), 

 wider than long (57 : 48) ; length to that of cephalothorax nearly as 1 : 4. 



Upper margin of furrow of chelicera with the three teeth as usual; 

 lower margin with three stout conical teeth which commonly de- 

 crease in size proximad. 



