250 Alexander Petrunkez'itch, 



ence of a semicircle of short hair, marking the end of the tibia 

 and the beginning of the interarticulate membrane between the 

 tibia and the metatarsus. Short hair is discernible on all joints 

 of the legs. 



Thomisus defossus Scudder {Text figure 20). 



Scudder, Tertiary Insects, 1890, p. 59, Plate 11, fig. 23 {$). 



One male from Florissant, No. 4742 (now No. 70) in the Scud- 

 der Collection of the Museum of Comparative Zoology of 

 Harvard University. 



Scudder's description is correct and all I have to add is that I 

 was able to expose the end of the third right tarsus and thus reveal 

 the presence of two curved claws (tcxtfigure 20). The left claw 

 is somewhat turned sideways and partly covered with what seems 

 to be hair but may be remnant of flat sharp-pointed ungual tufts. 

 The right claw shows distinctly a single median tooth. 



Figure 20 — Tlwinisus defossus Scudder. Specimen No. 4742 (70). Claws 

 of right third foot, x 135. 



FAMILY LINYPHIID.E. 



Characters of the Family : — Eight eyes in two rows, anterior 

 median eyes alone diurnal. Spinnerets approximated, preceded 

 by a colulus. Chelicerge with oblique margins. A stridulating 

 organ on the outer surface of the chelicer?e with a corresponding 

 part on the inner surface of the pedipalpi. No comb on fourth 

 tarsi. Clypeus high. 



