Abstract
As one of serial studies on the mechanical properties of spider threads, the effect of viscid droplet on their deformation behavior was investigated. The viscid droplets are regularly spaced on the spiral thread building orb web for capturing insects. It was shown that 1) the most abundant amino acid of the droplet is prolyne, while the component of the capture thread is not so different from that of dragline, 2) its surface tension is about 65mN/m which is comparable to that of water, and 3) although the capture thread deforms like rubber due to the existence of the viscid droplet, it behaves like dragline if the droplets are removed from it.
