The South-Equatorial Galaxy Catalogue (SEGC) by Harold G. Corwin, Jr. and Brian A. Skiff I. Introduction The "South-Equatorial Galaxy Catalogue" (SEGC) is an extension of the "Southern Galaxy Catalogue" (SGC; H. Corwin and A. and G. de Vaucouleurs, University of Texas Department of Astronomy Monograph No. 4, 1985), with data for RC2, NGC, and other generally large, bright, and nearby galaxies. SEGC, like SGC, is nominally "complete" for galaxies larger than 2.0 arcminutes at the 25.0 B-magnitude arcsec^-2^ isophote. This version 2.0 of SEGC features 1) J2000.0 positions precessed from the B1950.0 positions found in previous versions; 2) diameters and axis ratios reduced to the B = 25.0 magnitudes arcsecond^-2^ systems of RC3; 3) V-band magnitudes and B-V colors from RC3, or transformed from SDSS, ESO-LV, or 6dF photometric data; and 4) redshifts given as V = cz, usually taken from 6dF, but often from RC3, SDSS, or NED. It has been assembled primarily for use by amateur astronomers, but may find other uses as well. As we had for SGC, we intended to collect the data by eye from the IIIa-J plates taken with the UK Schmidt telescope. However, the extension of the southern Schmidt survey to the equator was not completed in time for the necessary prepatory work for "The Third Reference Catalogue of Bright Galaxies" (RC3; G. and A. de Vaucouleurs, H. Corwin, R. Buta, G. Paturel, and P. Fouque, 1991), so we used instead the glass copy plates of the first Palomar Sky Survey. These had the advantage over the POSS1 prints of lower photographic contrast (allowing us to see "further into" the centers of bright galaxies), but the disadvantage of frequent focus problems caused by the inability of the vacuum plate copier to pull the heavy copy plates into close contact with the positive "original". Originally, de Vaucouleurs had suggested the title "Extension" to the Southern Galaxy Catalogue (ESGC), but considering the different plate material, and the similarity of the acronyms SEGC and SGC (and the possible confusion of ESO with ESGC), we have decided to use SEGC for the general releases of the catalogue. The name "South-Equatorial Galaxy Catalogue", acronym "SEGC", and name format "SEGC JHHMMSS.d-DDMMSS" are all registered with the IAU name registration service (http://cdsarc.u-strasbg.fr/viz-bin/DicForm). Thus, the name for any included galaxy may be simply constructed from its J2000.0 sexagesimal coordinates. Earlier versions of SEGC which used B1950.0 positions may be cross-referenced to these latest versions by the included catalogue names (e.g. NGC, MCG, ESO, etc.), or by the "SEGC BHHMMSS.d-DDMMSS" version of the name included in the latest version. The earlist version of SEGC found its main use in the construction of RC3 by providing a check between the northern and southern diameter/axis ratio systems, represented by UGC/MCG, and ESO-B/LV, respectively. This gave added assurance that this system, as presented in RC3, is systematically consistent over the entire sky. The current version of SEGC is 2.0, and is found in the files "segc20.txt" and "segc20am.txt". The only difference between the two is that "segc20.txt" lists diameters as log(arcmin*10) and log(R) = log(D/d), while "segc20am.txt" has major and minor diameters in arcminutes. (The notes, not yet updated, are in a separate file still called "segc143.notes" to acknowledge its origin; this is discussed further below). There are 3333 entries, primarily for individual galaxies, but also for a few double or multiple systems where the objects are so closely interacting that data for indiviual objects could not easily be estimated. We have, however, attempted to give data for individual objects whenever possible. The data files, most recently assembled on a Macintosh computer, use only 7-bit ASCII characters, and have UNIX line endings. II. Catalogue Format. The data share a format similar to that of the SGC (which see), but some differences occur. There is one line per galaxy as follows for "segc20.txt": < RA J2000 Dec > < Name >< Type and Lum. Class >b lD fl slD lR fl sig b n bPA flb sig n Vmag f B-V q Sor cz Sor B1950 Name <> <> <--> <-> <> <> <------------------------------><----------------------->[<--><> <-> <--><> <-> ] | [<-><>] <> | <--->| <--->| <--> <---> <--> <--------------> Here are a few examples: 00 00 08.7 -06 22 28 MCG -01-01-016 Sa? pec? or I0? 1.14 0.60 1 168 1 13.36 0.85 6dF 6493 RC3 B235734.8-063910 00 00 21.6 -02 36 43 MCG -01-01-020 E+3: 1.24:: 0.19: 1 120 1 13.00 0.79 6dF 11365 6dF B235747.7-025325 00 00 26.7 -18 50 31 NGC 7807 SAB?(r:)b? 0.90 0.38 1 27 1 14.59 0.94 ELV 7655 6dF B235752.8-190713 00 01 57.8 -15 27 30 [RC2] A2359-15 = DDO 221 = WLM IB(s)m V 2.04 0.42 1 4 1 10.59 0.44 RC3 -120 RC3 B235924.0-154412 00 02 09.6 +02 56 26 NGC 7809 Im? 0.57 0.10 1 85: 1 15.14B RC3 19197 CfA B235935.7+023944 00 02 26.6 +03 21 06 NGC 7811 cIm: 0.57 .00 0.10 .00 2 155: 0 2 15.83 0.77 SDSS 7650 CfA B235952.7+030424 00 02 34.8 -03 42 37 MCG -01-01-024 SB?(s)bc I-II: 1.12: 0.19 1 5 1 13.56 0.72 6dF 6445 6dF B000001.0-035919 00 03 32.3 -10 44 40 NGC 7808 (R')SA:0o: 1.07: 0.00: 1 --- 1 13.48 0.85 RC3 8849 SDSS B000058.6-110122 00 04 00.9 -11 10 41 MCG -02-01-015 Sa? 0.55? 0.18? 1 10 1 16.85 0.52 SDSS 11474 SDSS B000127.2-112723 00 04 01.6 -11 10 28 MCG -02-01-014 SB:(rs)c II-III: 1.09 0.09 1 130: 1 13.36 0.22 6dF 11276 6dF B000127.9-112710 00 06 27.1 -13 24 54 NGC 7828 Im pec (Ring B) 0.85? 0.29 1 140 1 13.89 0.51 RC3 5660 RC3 B000353.6-134136 00 06 58.9 -06 57 18 MCG -01-01-034 SAB(s)dm IV 1.14 0.19? 1 50 1 14.55 0.95 SDSS 3885 HIPA B000425.3-071400 00 08 34.4 -10 56 58 MCG -02-01-028 SB(r)a 1.06 0.06 1 10? 1 13.56 0.32 6dF 9083 SDSS B000601.0-111340 00 11 06.7 -12 06 26 NGC 0034 = NGC 0017 Pec [1.15 0.29 ] 1 [ 30 ] 1 13.20 0.28 6dF 5931 RC3 B000833.5-122307 00 14 31.9 -00 44 13 UGC 00139 SAB?(s:)bc II: 1.33 0.53 1 80 1 12.86 0.27 6dF 3938 SDSS B001158.1-010054 00 18 51.0 -10 22 38 MCG -02-01-051 SB(s)b? pec 0.96: .05 0.29? .02 2 71 2 2 14.33 0.48 RC3 8110 SDSS B001618.1-103917 00 22 44.4 -06 41 05 MCG -01-02-007 Sd? pec sp 1.16: 0.49 1 173 1 1539 HIPA B002011.3-065743 00 25 29.7 -14 33 13 MCG -03-02-013 SB(s)d: sp II-III 1.23 0.76 1 81 1 14.77 0.65 SDSS 3399 HIPA B002257.7-144950 00 25 42.2 -08 17 01 NGC 0107 SB(s:)ab pec: II-III: 0.94:: .06 0.19: .03 2 135? 7 2 13.82 0.62 6dF 6266 6dF B002309.4-083338 00 26 54.8 -02 30 02 NGC 0113 SA:0- 1.15:: 0.13:: 1 135 1 13.16 0.67 6dF 4360 6dF B002421.3-024638 00 29 08.2 +02 48 39 NGC 0126 SB?0o: 0.78: 0.29: 1 110 1 15.22B RC3 4252 RC3 B002634.0+023204 00 51 17.3 -08 35 48 NGC 0277 S0- 1.14: 0.06:: 1 50:: 1 13.63 0.85 6dF 4411 RC3 B004845.7-085207 01 21 12.6 -09 12 41 NGC 0481 SA?(r:)0- pec 1.24: 0.13: 1 [ 40 ] 1 13.43 1.10 6dF 5518 6dF B011842.5-092823 02 39 29.3 -19 50 30 ESO 545- G 042 = MCG -03-07-049 Sm? IV? 1.26 0.31 1 14 1 13.96 0.85 ELV 4692 RC3 B023710.9-200323 03 19 07.1 -11 20 12 MCG -02-09-028 SB(s)dm IV 1.21 0.24 1 25 1 12.48 -0.45? 6dF 3184 RC3 B031643.5-113103 As noted above, "segc20am.txt" differs only for the diameters. Here are examples from the above list, with arcminute diameters rather than logarithms: 00 00 08.7 -06 22 28 MCG -01-01-016 Sa? pec? or I0? 1.4 0.3 1 168 1 13.36 0.85 6dF 6493 RC3 B235734.8-063910 00 00 21.6 -02 36 43 MCG -01-01-020 E+3: 1.7:: 1.1: 1 120 1 13.00 0.79 6dF 11365 6dF B235747.7-025325 00 00 26.7 -18 50 31 NGC 7807 SAB?(r:)b? 0.8 0.3 1 27 1 14.59 0.94 ELV 7655 6dF B235752.8-190713 00 01 57.8 -15 27 30 [RC2] A2359-15 = DDO 221 = WLM IB(s)m V 11.0 4.2 1 4 1 10.59 0.44 RC3 -120 RC3 B235924.0-154412 The columns are: 1) Position: RA in columns 1,2, 4,5, 7-10; and Dec in columns 12-14, 16,17, and 19,20. Mean positions for equinox J2000.0 are generally an informally-weighted mean from several sources (the sources are listed in previous versions of this introduction). The positions are presented in a single sexagesimal format: hh mm ss.d -dd mm ss These positions were precessed from the B1950.0 positions presented in the previous version 1.4.3 of SEGC. Equinox B1950.0 was used there as most of the source catalogues consulted during SEGC's initial construction during the 1980s carry B1950 positions. In addition, almost all of the positions measured for the included objects were referred to stars with positions on a frame defined by FK4 for which B1950.0 was the native equinox. A few large galaxies (e.g. NGC 6822, WLM) have overly-precise positions for ease of reading the electronic data file. Their estimated positions would be better represented by an "hh mm ss -dd mm.d" format. The positions given for all galaxies are always accurate enough to unambiguously identify the objects to which they refer. 2) Name in columns 23-54 (note difference from SGC): We have generally adopted these from the literature in, roughly, the following order of preference: NGC, IC, MCG, RC2, ESO, UGC, all others. We have constructed names for 35 galaxies without previous designations following standard IAU practice, adopting the numerical portion directly from the original B1950.0 position in the form SEGC BHHMMSS.d-DDMMSS. Several galaxies, "discovered" during the preparation of SEGC, have entries in subsequent catalogues (e.g. 2MASS, NPM1G); we have not hesitated to adopt these later names when they were available during final preparation of SEGC in 2008-2010. Finally, we often give additional names in this column to aid in the object's identification. We have almost always adopted NGC and IC names from Corwin's list in his NGC/IC position files (see CDS catalogue number VII/239A, http://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=VII/239A/ , and the latest available files at http://haroldcorwin.net/ngcic/ . If you find differences between SEGC and Corwin's latest files, use the identification in the latest NGC/IC files on his web site). Some NGC objects nominally in the SEGC zone are missing. These have such poor discovery positions that they are now unrecoverable (e.g. NGC 7666), they have confused identifications (e.g. NGC 1538), or they are asterisms (e.g. NGC 7453 is a triple star). 3) Type and Luminosity Class in columns 55-79: Morphological types are on the de Vaucouleurs revised Hubble-Sandage system as presented in "The Reference Catalogue(s) of Bright Galaxies" (RC1, G. and A. de Vaucouleurs, 1964; RC2, G. and A. de Vaucouleurs and H. Corwin, 1976; and RC3, G. and A. de Vaucouleurs, H. Corwin, R. Buta, G. Paturel, and P. Fouque, 1991; and in G. de Vaucouleurs, ApJS 8, 31, 1963). Also see "The de Vaucouleurs Atlas of Galaxies"; R. Buta, H. Corwin, and S. Odewahn, Cambridge University Press, 2007, for an updated, extended, and illustrated introduction to the VRHS types. We have used the RC2/3 version of the VRHS system -- EXCEPT that the "cD" galaxies, inserted by de Vaucouleurs at numerical type stage T = -4 in RC2/3, have been replaced with the transitional E/S0 types as in RC1 (the "cD" galaxies have been placed in their appropriate morphological type bins, generally one of the S0 stages). We have retained the RC2/3 compact elliptical galaxies at T = -6 and the compact irregulars at T = +11. A few dwarf ellipticals and spheroidals have a "d" prepended to their classifications. An ASCII underline symbol appears BEFORE the symbol that would, in normal text, be underlined. MCG -02-33-100 is an example: S_AB(s)bc pec II-III; this is closer to being a non-barred galaxy than a barred one. Luminosity classes in van den Bergh's system have, where possible, been assigned for spirals and irregulars later than Hubble stage "ab" (T = +2). As in SGC, we have extended the system to luminosity classes V-VI and VI (based on surface brightness estimates). We believe it is unlikely that these additional luminosity classes are correlated with fainter absolute magnitudes, but this has yet, to our knowledge, to be rigorously tested. Where there is more than one type estimate, we've simply averaged them. In general, then, the classifications we present here are compatible with those in SGC and in the Reference Catalogues. Note again, however, that we give appropriate morphological classifications to the "cD" galaxies that appear in RC2/3 at T = -4. We use the numerical stage T = -4 for true transitional types, E/S0, as de Vaucouleurs did in RC1. 4) Diameter in columns 81-84 and its standard deviation in columns 88-90: Logarithm of the major diameter in units of 0.1 arcminutes, or major diameters in arcminutes as explained above, reduced to the B = 25.0 mag arcsec^-2^ isophote using the RC3 formulae (see below). If the diameter was measured on more than one plate, the number given is an unweighted mean. Occasionally, diameter measurements by Corwin made on DSS images are presented for galaxies in close pairs or multiplets. These assume symmetry of the galaxy's image, and are always followed by the uncertainty symbol "?". Standard uncertainty symbols ":", "::", and "?" also often appear in columns 85,86 (and columns 98,99 for the axis ratios) when warranted by irregularities in the image. Common problems leading to uncertain diameters are the presence of irregular arms, plumes, and bridges; interacting companion galaxies; background or foreground galaxies; images of Galactic stars; uneven sky background on the plates (often real -- due to faint, diffuse nebulosity -- but sometimes due to large-scale plate defects); and, particularly for the early-type galaxies, uncertainty as to the maximum visible extent of the galaxy. If the measurement applies to more than one galaxy, or if it includes unusual extended features (e.g. "plumes", "jets", or "bridges"), it is enclosed in square brackets "[" in column 80 and "]" in column 105. Standard deviations in logD are given when two or more values were averaged. Note that these are given as logarithms even in the file "segc20am.txt" where the diameters are in arcminutes. 5) Axis ratio or minor diameter is in columns 94-97, and the standard deviation of logR is in columns 101-103: The log of the axis ratio logR = log(D/d) leads directly to the log of the minor axis, logd = logD - logR in the same log 0.1-arcminute units as the major axis, reduced to B = 25.0 magnitudes arcsec^-2^ (again following RC3). Uncertainty symbols (see above) following the axis ratio in columns 98 and 99 actually apply to the minor axis itself rather than to the axis ratio or its logarithm. The standard deviation in logR is given when two or more values were averaged. As with the diameters, these are given in logarithms even in the file "segc20am.txt", where the minor diameters are in arcminutes. 6) n(DR), column 107: The number of diameters and axis ratios used in determining the mean values. A blank here always means "1". 7) Position angle in columns 111-113, standard deviation in columns 119,120; and number of measurements in column 123: The position angle of the major axis of the galaxy's image, measured from north through east. Sometimes the major axis is not readily apparent, but a "principal axis" (for e.g. an inner isophote, or a bar) is; these are explained in the Notes for the object. All of the position angles in versions 1.4.3 and later of SEGC have been checked against the DSS images; position angles from earlier versions of SEGC were often incorrect and should be discarded. Position angles are generally given to the nearest five degrees, though some for flat galaxies are given to the nearest degree. If no position angle can be measured (e.g. for a round galaxy image), this column carries an em-dash (three ASCII hyphens) "---". As with the diameters and axis ratios, unweighted means and standard deviations (in columns 119,120) are calculated when more than one position angle is available for an object. Similarly, if the position angle applies to more than one galaxy, or applies to extended features ("plumes", "bridges", etc.), it is enclosed in square brackets "[" in column 110 and "]" in column 116. Occasionally, a position angle is noted to have two or more measurements in column 123, but no standard deviation is given. In these cases, the position angle was not measured on one or more of the plates, so the listed position angle is from a single plate. 8) V magnitude in columns 126-130, and color band flag (if not V) in column 131: The V-band magnitude, taken directly from RC3, or transformed to the RC3 system from other sources as follows: SDSS to RC3: Transformations (impartial relations) newly derived by me with SEGC data: mu <= 14.4: V(RC3)-13.5 = 1.10*[V(SDSS)-13.5] - 0.05*[mu(SDSS)-14.0] - 0.15, +- 0.20 mu > 14.4: V(RC3)-13.5 = 1.24*[V(SDSS)-13.5] - 0.83*[mu(SDSS)-14.0] + 0.37, +- 0.30 where mu is the surface brightness mu = V(SDSS) + 5.0*logD(SEGC) - 2.5*logR(SEGC) - 5.26 and the initial V(SDSS) magnitude is calculated from the SDSS g and r "model" magnitudes V(SDSS) = g - 0.59*(g-r) - 0.01 6dF to RC3: Again, the transformations are impartial relations newly derived by me with SEGC and SGC data: mu <= 14.7: V(RC3)-13.5 = 0.81*[Bj(6dF)-13.5] - 0.18*[Rf(6dF)-13.5] - ... ... - 0.09*[mu(6dF)-15.0] + 12.66, +- 0.35 mu > 14.7: V(RC3)-13.5 = 0.67*[Bj(6dF)-13.5] - 0.30*[Rf(6dF)-13.5] - ... ... - 0.82*[mu(6dF)-15.0] + 12.75, +- 0.50 where mu = Bj(6dF) + 5.0*logD_25(SEGC) - 2.5*logR_25(SEGC) - 5.26 The (B-V) color index transformation: (B-V)(RC3) = 1.06*[Bj(6dF) - Rf(6dF)] - 0.38, +- 0.20 ESO-LV: Buta and Crocker's (1992, AJ 103, 1804) updated RC3 transformation: B(BC) = 0.98*B(ESO) + 0.245, +- 0.27 R(BC) = 0.905*R(ESO) + 1.02, +- 0.21 and from the canonical B-R = 1.5(B-V) + 0.10 (see e.g. ESO-LV, page 15): (B-V) = 0.67*[B(ESO) - R(ESO)] - 0.07, +- ~0.1 Note that galaxies with low surface brightnesses (mu >~ 14-15) have a strong dependence on surface brightness itself in their SDSS and 6dF magnitudes. Neither, however, has a significant dependence on color, and only slight dependencies on galaxy type. The latter is absorbed by the surface brightness term in the above transformations as later types generally have lower surface brightnesses. Formal errors in the transformed magnitudes are given above for SDSS and 6dF. For magnitudes transformed from ESO-LV, "real-life" errors are estimated to be +-0.30 to +-0.35 magnitudes (see the RC3 introduction, p. 42, and Buta and Crocker, 1992). If the listed magnitude is not a V-band magnitude, the nominal band is listed in column 131. Currently, this is limited to just "B" for Johnson B, or "b" for B(j) measured on IIIa-J plates. The source of the magnitude and color index is given in columns 139-142. Other magnitudes were occasionally adopted. These so far include: B(j) from the APM (1990MNRAS.243..692M) flagged with a "b" in column 131. 9) B-V color index in columns 133-137, B-V caution flag in column 138, and magnitude and color index source in columns 140-143: B-V is taken from the same source as the V magnitude. Transformations to the RC3 system are via these equations: SDSS to RC3: (B-V)(RC3) = 0.98*(g-r) + 0.22 6dF to RC3: (B-V)(RC3) = 1.06*[Bj(6dF) - Rf(6dF)] - 0.38 ESO-LV to RC3: (B-V)(RC3) = 0.67*[B(ESO) - R(ESO)] - 0.07 The formulae for SDSS colors and initial V magnitudes, and ESO-LV colors are taken from published transformations for stars. These formulae are adequate for many galaxies, but those with emission lines in their spectra, or with significantly non-stellar slopes in the B and V filters, will have errors in the transformed color indices. The other equations, including those above for magnitudes, were derived from galaxy photometry, so are appropriate for these galaxies. Nevertheless, many color indices from these transformations (especially those from 6dF B(j) and R(f) magnitudes) are obviously discordant from colors expected for the galaxy types. We will replace these as new data become available. In the meantime, we have flagged the discordant colors in column 138, whatever their source, as follows: Color index Flag B-V < -0.2 d -0.2 < B-V <= 0.0 ? 0.0 < B-V <= 0.2 : 0.2 < B-V <= 1.2 [None; but we nevertheless advise caution!] 1.2 < B-V <= 1.3 : 1.3 < B-V <= 1.4 ? 1.4 < B-V d Highly-reddened low-latitude galaxies will have their B-Vs more or less strongly affected by interstellar extinction. Sources of the magnitudes and colors are (in order of preference): RC3 SDSS ELV = ESO/LV (1989) 6dF APM For galaxies without colors, approximate *unreddened* colors may be estimated from the morphological type: Type B-V Type B-V Type B-V Type B-V Type B-V E 1.0 S0/a 1.0 Sb 0.8 Sd 0.6 Im 0.6 S0 1.0 Sa 0.9 Sc 0.7 Sm 0.6 Other 1.0 These are obviously very uncertain, but may give you an idea of the visual magnitude if the galaxy has at least a B (or "b") magnitude listed. 10) Redshift in columns 147-151, and redshift source in columns 153-156: The recessional velocities from different sources show no obvious systematic differences on the +-50 km sec^-1^ level, so they are presented just as they appear in RC3, SDSS, 6dF, and ESO/ESO-LV. Some of the redshifts, however, were obviously discordant, e.g. three from SDSS were over cz = 100,000 km sec^-1^ and perhaps apply to QSOs near the galaxies. These and other clearly discordant redshifts were freely discarded, but almost all redshifts are retained here just as they were published. The redshift source (SDSS, RC3, ESO, and 6dF in that order of preference) is in columns 152-155. Other redshifts are from CfA = Huchra et al, 1999ApJS..121..287H HIPA = HIPASS, Doyle et al, 2005MNRAS.361...34D NED = NED selected heliocentric redshift, various sources Note that 6dF collected redshifts from 2dF, ZCAT (CfA), and SDSS as well as from their own observations. If the source is important to your work, see the 6dF documentation for more information. 11) B1950 name in columns 159 to 174. These are simply the B1950.0 positions from previous versions of SEGC turned into a "name" of the form "BHHMMSS.d-DDMMSS". These will allow easy reference back to the previous version should the need arise. While we encourage you to use the name that we have quoted in columns 23-54, or the B1950 "name", a J2000 "name" can be constructed from the J2000 positions that we have adopted. However, we caution that future versions of SEGC may well include improved positions. If so, "names" based on the current J2000 positions may be superceded. ------ Notes The Notes are in a separate file "segcnotes.txt". The format, unchanged from that in the previous "segc143.notes", is as follows: Name RA (1950) Dec Plt l Note <----------------------------><> <--> <-> <> <--> | <------------------------------------------------------> MCG -01-01-024 00 00.0 -04 00 1198 1 Short OX bar(?), vB pat inner arms, F outer arms. MCG -01-01-024 00 00.0 -04 00 1198 2 1st in grp. NGC 7808 00 01.0 -11 01 1193 0XN, pB lens, incomp R in F corona. S0 sp 2.9 sw. MCG -02-01-014 00 01.4 -11 27 1193 1 0XN, F arms. Optical(?) P(a) at 0.3 w MCG -02-01-015. MCG -02-01-014 00 01.4 -11 27 1193 2 -14 behind(?) -15. MCG -02-01-015 00 01.5 -11 27 1193 1 pS pB N, r': 0.3 x 0.18, pat arms, vF env. MCG -02-01-015 00 01.5 -11 27 1193 2 Optical(?) P(a) at 0.3 w MCG -02-01-014. NGC 7813 00 01.6 -12 15 1193 0XN, p smooth arms. Stage unsure. MCG -01-01-030 00 02.1 -08 22 1198 OXN, trace of r' in lens, F corona. 1st in grp. MCG -03-01-018 00 02.2 -16 19 365 S B N, pB bar, r: 0.45 x 0.4, pF pat arms. Name in columns 1-30: One of the names of the galaxy given in the "segc20.txt" file. Position in columns 31-44: An abbreviated B1950.0 position usually taken from the original SEGC work book. These are usually also the B1950.0 position in "segc143.txt" rounded off to 0.1 minutes of time and one arcminute, though final digit differences of 1 or 2 are possible. A tie-breaking letter, usually a compass direction ("n", "s", "e", or "w", or some combination thereof) is added when necessary. The format is thus HH MM.d -DD MMc. Plate number in columns 46-49: The POSS1 plate number on which the galaxy image was examined. Line number in column 51: If the note extends beyond one line in length, the lines are numbered (these are a computer sorting aid). Lines with no numbers indicate notes on a single line. Notes in columns 53-108: Finally, the note itself. Not all galaxies in SEGC have notes, but most do. Sometimes, these are a relatively elaborate description of the galaxy and its surrounding field, sometimes they simply note a feature of the object or a nearby companion. All measurements in the notes -- including rings and other features in the galaxy, distances on the sky between objects, etc. -- are in arcminutes unless specifically noted. Abbreviations are more or less standard, adopted from those in SGC, RC1, NGC, and other well-known (though now old) galaxy catalogues. ------ A simple analysis of the catalogue data will be presented later, but here is an "abstract". logD-logN plots show that SEGC is 50% complete at about logD = 1.2, but has a long "tail" to smaller diameters. ORIGINAL SEGC diameters and axis ratios may be reduced to the 25.0 B-magnitude isophote (RC3's standard diameter system) as follows (see the RC3 Introduction, Volume 1, Section 3.4, Tables 6 and 9) log D_25 = logD - 0.187, s.d. = 0.085, for T >= 0 log D_25 = logD - 0.157, s.d. = 0.093, for T < 0 and log R_25 = 1.26 * logR, s.d. = 0.08, for T >= 0 log R_25 = 1.11 * logR, s.d. = 0.07, for T < 0 NOTE AGAIN that the diameters and axis ratios given in "segc20.txt" and "segc20am.txt" have already been reduced to the B = 25.0 mag arcsec^-2^ systems of RC3. ------ Acknowledgments: We are indebted in particular to the late Gerard and Antoinette de Vaucouleurs for initiating the project, and for general guidance and inspiration throughout its duration. The University of Texas, Austin, Department of Astronomy; The University of Texas, McDonald Observatory; Lowell Observatory; and the California Institude of Technology, Infrared Processing and Analysis Center; all provided computing and other physical facilities, including the plates we scanned (POSS1, UT Austin; Pluto Camera, Lowell). NED, CDS, LEDA, ADS, HESARC, and STScI all provided invaluable access to on-line catalogues, the DSS, and the astronomical literature. We also benefitted from conversations with (in no particular order) Basilio Santiago, Michael Strauss, Will Sutherland, Barry Madore, George Helou, Marion Schmitz, Joe Mazzarella, Marianne Brouty, Georges Paturel, Brian Cuthbertson, and Ronald Buta. Finally, we thank Basilio Santiago for sending positions for objects observed in the Southern Redshift Survey, and Brian Cuthbertson for using his program "HyperSky" to provide many secure identifications for SEGC galaxies to which we referred our position measurements. Harold Corwin and Brian Skiff Latest revision 23 November 2019