The initial printing of the sheet of 50 3c value contains this (printing) design error. There was no space between Canada and the insects name. It was later corrected in the second printing. It occurs in the second row of the sheet on the left side. Position 11 to and including 14.
The 6c has an inscription error in all 4 corners which was noted but not changed.
All found in the Unitrade catalogue. You can also see this and other Canadian insect stamp errors in this series, and much more info, at Robins site
www.adminware.ca under elizabethan-era definitives under benefical insects.
Mike