One unclued light (hyphened) is a 38 of a word hidden in the grid. Two unclued lights are definitions of the hidden word, which is also the surname of a former 11 of 25 (two words), whose first name is an unclued light. The hidden word and its 38 — both starting in an appropriate square, and together forming a 38 relevant to the puzzle — must be highlighted.
 

Across

 
6    Divisions in Mississippi led by force aboard steamer (7)
13    Part screened by sign, a certain slender type (9)
15    Steep southern wood (4)
16    Cue card oddly came as a product (7)
18    Cross Australia westward, going around Perth finally (3)
19    Group of stars rested with band repelled by attention (10, two words)
21    Love of fine arts, bug endlessly consuming time (5)
24    Spot store’s latest pasta (4)
27    Work nut loose (4)
28    Hold gross reptile (5)
30    Stories about doctor operating mostly in stretches? (10)
33    Piece of advice in extremity (3)
35    Hunter in routine period (7)
36    Film covering search for bone (7)
37    Man leaves seat to get oil (4)
39    Irritable knight, ardent, missing maiden (10)
40    Test nag, terribly laden (7)
41    Class for example rejected by students (5)
 

Down

 
1    Growing inclined to restrict mischievous child on day before vigil? (14, hyphened)
2    Promises to work for taskmasters? (8)
3    Desert plant in Egypt surrounded by divine incarnation (6)
4    Are ceremonies disrupted by native fire-raisers? (9)
5    Rebuke soprano without passion (5)
6    Quiet, confused about officer being sentimental (8)
7    Hook knocked about hard (5)
9    Wrenches ragged drapes covered with flies (14, two words)
10    Umbellifer among mosses eliminated (6)
12    Love, strange, alas not reciprocated (6, hyphened)
14    Plunder inside according to investigator (6)
20    Sticky around muscle before removal of fatty tissue (9)
23    Production price sadly is not cut (8, two words)
26    Enter church after support (6)
29    Busybodies turning up in courts (6)
31    Stick machine on base (6)
32    Baron makes public attacks (5)
34    Translation of Bible necessary to limit alarm (5)
35    Meat, not good for sheep (5)
 
A first prize of £30 for the first correct solution opened on 17 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 2222, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.