Q. Bracketed Keys to identifying plants and animals?
In bracketed keys two couplet leads of the same rank are bracketed together. The alternative clues or couplets are written or printed in adjacent lines and reference to their successive subordinate clues is given by number mentioned at their end.
The leads in the format could be numbered in alphabets viz. A and AA for 1 and 1' and 1' or 1' lb or B and BB for 22' or 2a 2b but the number of alphabets is restricted to 26. In case large groups where more than.$ couplets are needed the alphabets cannot serve the purpose and we have to use the numbers which can go up to any extent.
In indented keys the groups of one lead are disposed off first with the help of indented leads and the related taxa come together.