Production

There are seven types of silk produced by seven silk glands.  A single spider does not possess all seven glands but has at least three if it is male (dragline, attachment and swathing silk) or four if it is female.  The additional one is for egg sac silk.  The seven types of gland are:

• Achniform gland: swathing silk.

• Cylindriform gland: egg sac silk.

• Ampullate glands (major and minor): non-sticky dragline silk.  Silk from the minor ampullate gland is only half as strong as that from the major gland.

• Pyriform gland: attaching threads - attachment discs are made which anchor a thread to a surface or another thread.

• Flagelliform gland: core fibres of sticky silk.

• Aggregate gland: outer part of sticky silk - droplets of an adhesive substance are deposited along the threads.