170 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



part, attached to the under side of stones or spun within rugosities of the 

 bark of trees. They have often bright colors, and are found covered 

 with mud. Among Saltigrades and Laterigrades, all species appear to 

 have the habit of thus disposing of their cocoons. 



IV. 



4. A fourth point of comparison is the method of protecting cocoons. 



When we come to consider the modes of protecting cocoons, we find much 



variety, and the various methods well represented among all 



Protec- Tribes, modified by differences in habit characteristic of the 



i / 



i 10 R groups represented. The chief modes of protection are, first, by 



Lines lines, within which the cocoons are spun and w r hich form an 



interlacing barrier of threads around them. This mode has many 

 representatives among Orbw r eavers and Lineweavers; is occasionally repre- 

 sented among Tubeweavers, as with Dictyna and Segestria ; occasionally 

 among the Citigrades, as Dolomedes and Pucetia ; but is unknown among 

 Saltigrades and Laterigrades. 



The second mode of protection is by leaves, which are drawn over the 

 cocoons. , This is either done by attaching the cocoon to a single leaf and 



then curling the edges thereof around it, or by forming a sort 



' y of bower of several leaves united at the points and edges, and 

 Leaves. . . . , . , . ,. . 



spinning within this cavity a maze of interlacing lines, within 



which the cocoon is hung. This method of protection is well represented 

 among Orbweavers. Among Lineweavers it is seen in our Theridium dif- 

 ferens, and in certain European species of Theridium, as T. nervosum, 

 T. riparium, and T. lineatum. Among Tubeweavers it largely prevails, Aga- 

 lena, at least, practicing this method. Dolomedes represents the Citigrades, 

 making a beautiful bower, within which her cocoon is hung. The Salti- 

 grades frequently thus protect their cocoons; and among Laterigrades, 

 Thomisus, Sparassus, and Philodromus. 



The third method of protection is by silken tents and tubes. This is 

 sparingly practiced among Orbweavers. Among Lineweavers, as far as I 

 know, it is only used when the silken tent is enclosed within an 

 T ts d ou ^ er covering of leaves. Among Tubeweavers it has a wide use, 

 Tubes Herpyllus, Ariadne, Drassus, Clubiona, and others of like spin- 

 ning habit practicing it probably without exception. I know of 

 no Citigrades that thus protect their cocoons, unless we consider the burrow 

 and home as a cocoon tent or den, and it certainly does serve that end. 

 But among the Saltigrades the habit is general, Phidippus, Attus, Syna- 

 gales, Synemosina, and all known genera protecting their cocoons with an 

 outer silken cell, within which the mother dwells. Among the Lateri- 

 grades, Thomisus and Sparassus have the same habit. 



The fourth method of protection is by an armor of extraneous ma- 



