104 PECKHAM. [Vol. 1, 



are mimicked by otliers that are soft), spines could scarcely be 

 imitated by a soft-bodied creature witli sufficient accuracy to 

 insure disguise. 



While spiders most commonlj^ mimic ants, we hear also of 

 their imitating beetles, snail-shells, ichneumons and horse-flies. 

 There is also a curious Madagascar species which looks exactly 

 like a little scorpion, the resemblance being heightened by its 

 habit of curving its flexible tail up over its back when irritated. 



Those that resemble beetles comprise nearly all the species 

 of the genera Coccorchestes and Homalattus. These are small 

 spiders with short, convex bodies. The abdomen fits closely 

 over the cephalothorax and the epidermis, which has usually 

 a metallic lustre, is sometimes coriaceous. Striking exatoples 

 are found in H. coccinelloides, which bears a strong resemblance 

 to beetles of the family Coccinelloidte and in C. cupreus, in 

 which certain marks on the abdomen imitate the elytra of 

 beetles. 



The following account of a spider which mimics a snail- 

 shell is given by Mr. G. F. Atkinson : 



"An undescribed species of Oyrtarachne* mimics a snail- 

 shell, the inhabitant of which, during the summer and fall, is 

 very abundant on the leaves of plants in this place. In the 

 species of Cyrtarachne the abdomen partly covers the cephalo- 

 thorax, is very broad at the base, in this species broader than 

 the length of the spider, and rounds off at the apex. When it 

 rests upon the under side of a leaf with its legs retracted it 

 strongly resembles one of these snail-shells by the color and 

 shape of its abdomen. The two specimens which I collected 

 deceived me at first, but a few threads of silk led me to make 

 the examination. The spider seemed so confident of its protec- . 

 tion that it would not move when I jarred the plant, striking it 

 several hard blows. I pulled the spider forcibly from the leaf, 

 and it did not exhibit any signs of movement until transferred 

 to the cyanide bottle." f 



*C. multilineata. 



iNeiD Instances of Protective Sesemhlances in iSpiders, American Naturalist, 

 June, 1888, p. 545. 



