Iq 1820

[hankir]

An extra letter in the clue to be removed before solving.

2. Herbs spread around behind mill stream (11)
12. Source of dye left owing to unfortunately missing colour in supply (7)
6. Hopeful fantasist in decline, assuming curses returning (7)
9. Morag’s very big squeal linked with seaweed (8)

Thanks.

[ProfessorMaisie]

2a '[m]ill' = anag 'stream' (then reverse) STROW = 'strew' archaic [m extra].
12a 'left [o]wing' to 'u(nfortunately)' missing from COLO(u)R IN 'supply' = anagram indicator.
6d 'decline' = WANE with BAN = 'curse[s]' reversed inside.
9d SING = 'squeal' 'lin[k]ed with' KELP.

[hankir]

Thanks, ProfessorM.
Had guessed 2 and 12 but did not know how to parse.
My 16a is Salt deposit. If Horror is the extra word, then my answer has 2 letters missing.
for 30a, I have 4 letter word for level and same as extra word. But then my 9 letters do not make any sense,

[ProfessorMaisie]

16a is an anagram of '(h)OUR(s)' + A and 'horror' is the correct word to drop - giving 'h' as the not-used letter, hankir.
30 - yes, it is 'same' that's removed (the answer sounds like 'raise', and the not-used letter is 'm').

[hankir]

Thanks ProfeesorM.
I was picking the wrong letters.
What does the extra letters in thematic order mean?

[ProfessorMaisie]

It's hard to make sense of 'thematic order' until you know exactly what you're looking for, hankir - and you'd be pushed to find the theme even if you spotted it!
I got all 9 not-used letters first (they're in order and give the title of a collection of poems). Using the name in the puzzle title + this word will get you started.
The theme works a bit like a russian doll, look around the edges and then see what's in the centre (11 letters).

[Cillagoose]

Can't find a word to fit 4d. Must have one wrong.
Tip for parsing 4d please?

[ProfessorMaisie]

4d def is first word - abbrev ('small') for 'sustained' musically (3 letters) + anag CA(b)INS with 'E(arth)' taking over from 'bas[i]s' = 'b'.
'

[hankir]

Thanks ProfessorM.
But I give up at this stage.

[Cillagoose]

Thanks from me too. I had misspelled the unusual word at 12a. Just last letter of 20a to get now.

[ProfessorMaisie]

Last letter of 20a 'y'.
If you're still tempted, hankir - 'har???ium' + name.

[hankir]

Thanks ProfessorM.
Had to go away for a while.
I have Harmonium and Wallace Stevens but no idea what to do.

[hankir]

There is a museum with title items in London.
Donated by Marquess RW.

[Cillagoose]

I don't think that's relevant, hankir.
Look at the items in the poetry collection, - there are lots! But one stands out as lovely for a crossword setter.

[Cillagoose]

And it has more than 29 letters in the title.

[hankir]

Thanks Cillagoose.
I was looking at the extra letters and saw 11 word insects inside an amphibian and so on. I found the poem.
That is clever.

No wiser yet what to highlight.

[Cillagoose]

They aren't easy! One is.
There is some symmetry. Or regularity, in the rows.

[hankir]

Thanks Cillagoose.
I willpick this uptomorrow.
I have made it farther than I thought, so can wait for 2 weeks.

[Cillagoose]

You've got it.