Thanks to you both. I was deceived by "Northern" in 25a, blithely assuming it simply indicated "N" in the wordplay. Presumably it's actually part of the definition, as "AG" is a specifically German abbreviation for a joint stock company.
I was a bit confused by comments on AB that one member is missing from the complete set. If I'm right there are 13 members in the original work - 8 of these appear in the grid and the other 5 appear as letter jumbles in the clues. Would others agree, if not, which one is missing please ?
I agree - together with the 5 from the consecutive letter jumbles in the clues that seems to make a full set of 13 animals. Someone on AB suggested that the setter had failed to include another character in the grid, but surely there were no others ?
There is (almost) a character at 20 across connected to Jessie and one of the eight letter ones.
For Clover put an e into third place in the original clue answer.
Stuck on a few "normal clues" if anyone can help please:
20a Club singer -- a hooker (7) ???C?ER
20d Hard wood set off hard nut coverings (7) ???M??S
41a tests openings in the place of the seal (5) O??LS
possibly "orals" but how does it parse?