Across:
8 Ran away from Greenland (‘ran’ away from ‘Greenland’ = geenld = LEGEND) or that’s the myth (LEGEND),
9 Sensible (RATIONAL) quota (RATION-) for a (-A-) Liberal (-L) (RATIONAL),
10 Sounds like (= homophone indicator) delivery of mail (delivery of ‘mail’ = ‘male’ = SON-) from Government (-G) (SONG) in record number (SONG),
11 Those part of a smear campaign (INNUENDOES) heard (= homophone indicator) in (‘in’ = ‘inn’ = INN-) Spain (-E-), divided a French (French ‘a’ = un = -U-N-) party (-DO-) and half the viewers (eyes) (half the ‘eyES’ = ES) (INNUENDOES),
12 Unit (-I) finding genetic material (DNA = -AND-) in Mercury (HG = G-H-) Rising (= reversal indicator) (GANDHI) for old statesman (GANDHI),
14 Very aggressive types (PIT BULLS) built (built = -IT BUL-) complex (= anagram indicator) in place (P-L-) beside school (-S) (PIT BULLS),
15 25 (‘national’ = NATIONAL) and 26 across (‘anthem’ = ANTHEM-) open the set (open the ‘Set’ = -S) (NATIONAL ANTHEMS) with country music numbers (NATIONAL ANTHEMS),
18 Local fruitcake (‘local’ fruitcake = HEADCASE) from Schull (‘Schull’ = ‘skull’ = head case = HEADCASE), by the sound of it perhaps (= homophone indicator),
20 Phrenologists missing, in short (‘phrenologists’ missing ‘in short’ = pelogs = GOSPEL), and that’s the absolute truth (GOSPEL truth),
22 Contempt (DISRESPECT) in crushing (= anagram indicator) spiders, etc. (spiders etc = DISRESPECT),
24 Got (got = TOG-) upset (= reversal indicator) at school (-S) (TOGS) – someone was using them to test the waters (TOGS),
25 A person from America for instance (NATIONAL) produced, for example, turkey (Turkey = NATION-) from Alabama (-AL) (NATIONAL),
26 Worker (ANT-) on the border (-HEM) (ANTHEM) similar to 10 across (‘song’ = ANTHEM).
Down:
1 That’s old hat perhaps (FEDORA) to Iron (iron = FE-) Lady (-DORA) (FEDORA),
2 Mass on the open sea (BERG) – those on the Titanic would rather have avoided it (iceberg / BERG),
3 One of the tables (ADDITION) similar to most of those in 24 down (most of ‘tots’ = tot = ADDITION),
4 The limits of Grigori Rasputin’s (the limits of ‘GRigori RasputIN’ = GRIN) amused look (GRIN),
5 Parade (STREET) of various (= anagram indicator) trees (trees = STREE-) from the bottom of the forest (bottom of the ‘foresT’ = -T) (STREET),
6 For those known for their prospects (GOLD RUSHES), Bolt’s (bolts/dashes = RUSHES) after (= positional indicator) the medal for winning the race (GOLD RUSHES),
7 Meeting (DATE) Deep Purple (PLUM) (DATE PLUM) with Sharon Fruit (sharon fruit/persimmon = DATE PLUM),
13 Dates (DRIED FRUIT) doctor (DR-) that is (i.e. = -IE-) in front of Daphne (in front of ‘Daphne’ = -D) and Olive (FRUIT) (DRIED FRUIT),
14 Pressure (P-) to take drugs (-U-SE) over heart (centre = l) complaint (centre of ‘compLaint’ = -L-) (PULSE) is a vital sign (PULSE),
16 New Yorker (AMERICAN) produced article (A-N) about unstable (= anagram indicator) Crimea (Crimea = -MERICA-) (AMERICAN),
17 Odd (= anagram indicator) thing (thing = NIGHT-) for accountant (-CA-) to post (-P) (NIGHTCAP) with late tot (late tot/drink = NIGHTCAP),
19 Rim from brain stem (‘rim’ from ‘brain stem’ = banste = ABSENT) is missing (ABSENT),
21 Legate (legate = EAGLET) travelling (= anagram indicator) with young high-flyer (EAGLET),
23 No end to the needles (no ‘end’ to the ‘needles’ = eles = EELS) for the long swimmers (EELS),
24 Caught up (= reversal indicator) in Aristotelian (in ‘ariSTOTelian’ = stot = TOTS) nursery group (TOTS).