The unclued Across lights become thematic when a suffix is appended. The individual unclued Down lights (one a proper noun) also become thematic when a different suffix is appended; 1 Down consists of three further words which individually become thematic in the same way as the unclued Down ones do. The unchecked letters of all these unclued lights reveal HADDOCKS’ HERB GARDEN LTD. Elsewhere, ignore an apostrophe.
 

Across

1    Call for dismissal (5)
4    17s very bold pieces (9)
9    Badly undernourished — not used to school break (10, two words)
11    Geographical feature’s picture surround (5)
12    First to arrive on time, injured a bird or reptile, say (7)
15    Outsider in Dáil Éireann oddly absent (5)…
16    … out with Liberal having direct family connections (6)
21    Amateur bursting into song midway — so detestable (8)
22    Line on map which has no letters repeated (7)
27    No raids? Quite wrong! (7)
28    Natural alloy chosen by young lad (8)
33    Copper taking note, wearing gold eyepiece (6)
34    Fluid retention an ancient Persian rejected (5)
37    Having more space and sounding colder? (7)
38    Silver destroyed semi-precious stone (5)
39    They sound like grim stories! (10, two words)
40    A. Boult ran wild in capital (9, two words)
41    Some courtyard enclosing woodland (5)
 

Down

2    Bird of gang member (should be hugged!) (6)
4    French delicacy — small hard things? (6)
5    First bird in winter nest (4)
6    Physical relationship could be sham and low (7, two words)
8    Highly favoured French art was in abundance (8)
10    He may fit a brace and awkwardly reload sten gun (13, two words)
13    Popular prisoner showing sign of hesitation when ruling (7, two words)
15    Spenser’s suddenly tailed goddess (6)
17    Mason’s reset his post that’s a mousetrap (6)
18    Donkey, for one, bearing trap in Tyneside (6)
19    Can be viewed mid-week in black (7)
20    Endlessly variable South African plant (6)
23    Dressing a little boy in manure (8, two words)
26    Medic holding pink and a sundew (7)
29    US cat of endless courage, wandering (6)
36    Aware of Oregon’s outside temperature — zero! (4)
 
A first prize of £30 for the first correct solution opened on 14 August. There are two runners-up prizes of £20. (UK solvers can choose to receive the latest edition of the Chambers dictionary instead of cash — ring the word ‘dictionary’.) Entries to: Crossword 2320, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.