20 THE WAY LIFE BEGINS 



down the back. Near the head are four larger, orange-red, 

 tubercles decorated with black spines. The caterpillars are 

 well worth looking for, yet, as you can imagine, they are not 

 easily found. Their color helps them to hide in the green 

 foliage upon which they feed. 



Spinning the Winter Home 



When the time comes for the caterpillar to change to the 

 chrysalis, it loses its bright color. A twig is sought and prepa- 

 rations are made to spin the cocoon. The caterpillar holds 

 fast with its strong back feet and reaches forward as far as 

 the long, strong body will permit. From a tiny silk tube 

 in the lower lip are spun the first supporting lines. These 

 silk threads are very strong, and give the caterpillar his 

 familiar name of 'American Silk Worm'. The first lines form 

 a frame-work upon which is fastened other threads, until the 

 outer wall of the cocoon is completed. This usually takes 

 on much the shape of a hammock. The threads are woven 

 at first into a cream-colored fabric, but this darkens on 

 exposure. Within the hammock the spinning continues, 

 until the caterpillar has woven an inner chamber of much 

 finer mesh, separated from the outer, protecting layer by a 

 space filled with loosely woven threads. The air chamber 

 between the outer and inner layers makes the inner cell less 

 liable to sudden changes of temperature. The weaving of 

 this inner cell is hidden from view by the outside coat. Within 

 the inner chamber the caterpillar rests after its spinning work 

 is done. Finally, the caterpillar wriggles out of its skin for 

 the last time. An examination now of the inside of the finished 

 cocoon will reveal the transformation which the caterpillar 

 has undergone in becoming a heavy, dark brown chrysalis. 



Examining the Chrysalis 



If you desire to make this examination of the chrysalis, 

 cut carefully through the two silken covers. This will be 

 no easy task, for they are surprisingly tough. They were 

 made to shed the snows and rains of winter, and are tight 

 enough to keep out the cold winds, and tough enough to 



