Notes. Abundances in Cols. 4 and 5 are 12+log[O]/[H] and 12+log[C]/[H], respectively. In Cols. 6 through 8, total hydrogen column densities were derived assuming a carbon dust grain depletion factor of 0.5. In Cols. 10 through 13, values marked with subscript h are derived with correction for the HI contribution in Col. 9 for galaxies with a tilt b/a ≥ 0.6; a contribution N(HI) = 0.5 × 10²¹ (see text) was assumed for all other galaxies including those lacking HI data. Mass listed is total hydrogen mass; to obtain total gas mass, multiply by 1.35. I(CO) is taken from Table 2. E(xtrapolated) is the lower limit assuming the extrapolated carbon abundance from Col. 5; G(alactic) is the upper limit assuming solar neighborhood carbon abundances; N(ominal) is the most representative intermediate carbon abundance discussed in the text. The small galaxies NGC 3310, NGC 4631, and NGC 4826 have much lower abundances than the other galaxies; for these we set N equal to G. Superscripts ⁴⁰ and ⁸⁰ denote results for isotopological abundances [¹²CO]/[¹³CO] = 40 and [¹²CO]/[¹³CO] = 80, respectively.

References. References to HI data: (1) Lucero et al. (2015); (2) Puche et al. (1991); (3) Knapen et al. (2004); (4) Stanford (1990); (5) Shostak & van der Kruit (1984) (6) van Driel et al. (1995); (7) Swaters et al. (1997); (8) WHISP database, https://www.astro.rug.nl/~whisp/ (9) Hurt et al. (1996); (10) Brinks et al. (1997); (11) Ondrechen et al. (1989b); (12) Ondrechen & van der Hulst (1989a) (13) Jörsäter & van Moorsel (1995) (14) Crosthwaite et al. (2000); (15) Hibbard et al. (2001); (16) Dahlem (1992) (17) Saikia et al. (1990); (18) Taramopoulos et al. (2001) (19) Wevers et al. (1986); (20) Yun et al. (1993); (21) Irwin & Seaquist (1991) (22) Mundel et al. (1995); (23) Mulder et al. (1995); (24) Kregel & Sancisi (2001); (25) van Moorsel (1983); (26) Zhang et al. (1993); (27) Wilding et al. (1993); (28) Stanford & Wood (1989); (29) van der Hulst (1979)’ (30) Liszt & Dickey (1995); (31) Verheijen & Sancisi (2001); (32) Warmels (1988); (33) Cayatte et al. (1990); (34) van Albada (1980); (35) Chung et al. (2009) (36) Knapen et al. (1993) (37) Braine et al. (1993b); (38) Rand (1994); (39) Mulder & van Driel (1993); (40) Braun et al. (1994); (41) Ott et al. (2001); (42) Tilanus & Allen (1991); (43) Tilanus & Allen (1993); (44) Irwin (1994); (45) Baan et al. (2007); (46) Tacconi & Young (1986); (47) Haan et al. (2008); (48) Bosma (1981); (49) Chengalur et al. (1994); (50) Smith & Wallin (1992). References to abundance data: (A) Vila-Costas & Edmunds (1992); (B) Zaritzky et al. (C) Skillman et al. (1996); (D) Moustakas & Kennicutt (2006); (E) Moustakas et al. (2010); (F) Robertson et al. (2013); (G) Pilyugin et al. (2014).