Possible Clues:

• How a 18 down may may positively get to be six feet long
• A crazy set-up a worker will find very hard
• One may be positive that this was the first of all the insects
• One may be positive that that was the very first insect
• Inflexible, obdurate
• Can one be so positive that that's an insect mother?
• Insistent, inflexible
• Can one be so sure that this was the father of all insects?
• Positive and unrelenting
• Far from easygoing