110 PECKHAM. [Vol. 1, 



Synageles picata ( fig. 11), while not a rare spider 

 with us, is not often caught in the sweep-net, as it usually 

 keeps close to the ground. One hot afternoon in July, how- 

 ever, while sweeping on a sunny, stony hillside, sparsely covered 

 with grass, I captured five females and 

 one male of this species along with eight 

 or ten ant-like beetles and a dozen or 

 fifteen small ants of two or three different 

 species. Being anxious to discover what 

 relations existed between these creatures, 



FlB. 11.— Svnageles plc- 



L '^KumHenf "^'^''' '^'^ ^''' which, thougli belonging to different 

 orders, bore so strong a resemblance to 

 each other, I put them all together in a glass-covered box. 

 The results of this experiment were negative. The spiders, 

 while greatly interested in each other, paid but little 

 attention to the beetles and none at all to the ants. The ants 

 ran wildly about and seemed to be entirely absorbed in trying 

 to get out. The beetles took matters more philosophically and 

 kept quiet. 



After several hours I put some gnats into the box. 

 These were caught and devoured by the spiders. A little later 

 I liberated the ants and beetles. The spiders lived in the box 

 in good health and spirits for the remainder of the sum- 

 mer. They were very fond of heat, running about very 

 actively as long as their box stood in the sunshine, but retir- 

 ing into their little, tubular nests as soon as it became cool or 

 cloudy. 



While picata is ant-like in form and color, by far the most 

 deceptive thing about it is the way in which it moves. It does 

 not jump like the other Attidae, nor does it walk in a straight 

 line, but zig-zags continually from side to side, exactly like an 

 ant which is out in search of booty. This is another illustra- 

 tion of what Wallace has shown in relation to butterflies — that 

 that which is an important functional structure in the 

 mimicked group may be imitated by the mimetic species, 

 even when the habits of the latter render it perfectly 



