262 PROCEEDINGS OF THE ACADEMY OF [March, 



scription and interpretation. What is needed above all, as the pre- 

 liminary to any morphological or Inroad ethological study of them, 

 are full and ample descriptions of the structure— of the external geni- 

 talia, together with the form and proportions of the cephalothorax, the 

 mouth parts and the legs. The number of the teeth on the tarsal claws 

 is of no value, for it is subject to great individual variation, as has been 

 shown by ni}^ student, Mr. Carl Hartmann. The number of teeth 

 on the chelicera is of more importance, but must be used cautiously 

 and at the most as a specific character, for I have found a specimen 

 of TrocJiosa purcelli where one cheliceron differed in the number of 

 its teeth from the other. The number of spines on the joints of the 

 legs may not be greatly subject to individual variation, but in very 

 closely related species it ma}^ differ, as e.g., the spines of the ventral 

 surface of tibia I in Pardosa. Characters of the relative position of 

 the eyes are decidedly variable in different individuals of some species, 

 apparently constant in some others. Again, some species, particularly 

 of Trochosa and Pirata, show consideral^le secondary sexual structural 

 differences. And the epigyna even, perhaps the best of any single 

 structural character, are often variable in their form. 



In the present paper I give descriptions of the structure of all those 

 species seen by me, with figures of the genitalia in those cases where 

 they have not been figured before or where the figures have been badly 

 made, and descriptions of the color and dimensions only in the case of 

 new species or where preceding descriptions were not detailed. Where 

 such descriptions conflict with those of my previous papers, thej- are to 

 be considered as emendations of the latter. In the measurements of 

 the legs the coxse are included; and b}^ the term "height of the head 

 in front" is meant the distance from the inferior margin of the clypeus 

 to the superior border of the eyes of the second row. Onl}^ writers 

 who have given descriptions are included in the synonymical list of 

 each species. All the species previously described by me are described 

 again, but in their structure much more in detail than before; also 

 all the species described by Emerton (1885), except his Lycosa nigro- 

 ventris and Pirata insularis, are described ; and in the Keys all the spe- 

 cies from the continent of North America described by Kej'serling 

 (1876) are included. No species have been considered from the North 

 American continent south of the United States. With great care I 

 have gone over again the previous descriptions of all the species from 

 this region, but unfortunately the following papers were inaccessible 

 to me: Banks (1894a), Blackwall (1846, 1871), Cragin, Giebel (1869), 

 Girard (1854) and Thorell (1872). Doubtless on accoimt of these 



