342 Wisco7ism Academy of Sciences^ Arts^ and Letters. 



Dynamiiis gratus, sp. nov. 

 PL XXV, figs. 8-8a; PL XXVI, fig. 10. 



Length ^ 5 — 5.5 mm. Legs, 3421. 



This species is rather small for Dynamius. Looking at it 

 under alcohol it has a long black cej)halothorax, with wide white 

 bands on the sides, and a short dark abdomen, Avith three trans- 

 verse white bands, one in front, one behind, and one across the 

 middle. All the legs are iridescent, especially the first, on the 

 tibia and patella, but they have no heavy fringes. The thoracic 

 part is flat for some distance behind the dorsal eyes. The eyes 

 of the second row are half wav between the lateral and the dorsal 

 eves. 



When the spider is dry, bright red hairs appear around the 

 eyes of the first rovr, and all over the clypeus, excepting a narrow 

 white line at the margin. We also find a few patches of white 

 hairs left on the black cephalic part. The front part of the 

 abdomen is occupied by a band of white hairs, behind which are 

 some yellowish hairs, and behind this again, is a region that is 

 jet black. Across the middle is a wide white band, then more 

 yellowish hairs, and then an indistinct band of white hairs. 

 The falces are small, brovm, vertical, with a few white bristles. 



So far as coloring is concerned it is difiicult to distingaiish this 

 species from parvus. In both species the cephalic part is very 

 slightly inclined, but while in gratus the flat portion of the 

 thorax occupies four-fifths of its length, in parvus it occupies 

 only about one-half. The relative length of legs is different, 

 and while the white hairs on the femur of the palpus are long in 

 parvus, they are short in gratus. 



Linus P., 1885. 



PL XXV, figs. 5-5b. 



The cephalothorax is very high, with the sides almost vertical 

 and parallel. It falls sharply in both directions from the high- 

 est point, at the dorsal eyes. The quadrangle of the eyes is one- 

 fourth wider than long, is wider in front than behind, and oc- 

 cupies one-half of the cephalothorax. The first row, which is 



