Appendix A: Notes to Table 1

FGC 1 The Sb spiral MCG-01-01-028 is at a projected distance of $16\hbox{$.\mkern-4mu^\prime$ }9$ from FGC1 and has V=3813 km s^-1 (Huchra et al. 1993), although it should have been well outside of our beam and no H I detection of MCG-01-01-028 has previously been reported. Our narrow H I profile is consistent with the Sm classification of FGC1. An uncatalogued dwarf was also present in the beam.

ESO 350-005 An additional marginal detection was also present at $V_{\rm h}\sim3689$ km s^-1 with $W_{20}\sim225$ km s^-1, and $S\sim1.6$ Jy km s^-1.

FGC 45 Although our detection is weak, it also appears in independent observations obtained with a different center velocity and velocity resolution, hence we believe it to be real.

FGCE 62 The narrowness of our detected H I profile and its low recessional velocity raise some doubt as to whether we have detected FGCE 62 itself, which has an Sd classification and rather small angular size (D₂₅ =  $0\hbox{$.\mkern-4mu^\prime$ }8$); numerous other uncatalogued galaxies are visible on the DSS within the projected Nançay beam.

UGC 1461 Our detection of this source is rather marginal, but its validity was reconfirmed by Giovanelli et al. (1997).

FGC 202 Very low surface brightness appearance on the DSS.

FGC 273 Numerous galaxies are present in this field, most of which do not have published redshifts. It is unclear which, if either, of our detected line profiles corresponds to the target.

UGC 2382 The gap near the center of detected line profile is likely an artifact caused by the overlap of two autocorrelator banks; as a result, the integrated flux of the profile may be underestimated.

FGC 382 Our H I profile is single-peaked and appears rather dwarf-like for an Sd galaxy, but there is no obvious candidate for an interloper on the DSS. The S0/a NGC 1204 at $16\hbox{$.\mkern-4mu^\prime$ }6$ away has an optically-derived radial velocity of $V_{\rm h}=4282$ km s^-1 (Da Costa et al. 1998), but it should have been well outside our beam. In addition, we have obtained both Nançay and Green Bank observations of FGC 382, and the fluxes and linewidths of both observations are consistent within errors in spite of the differing beam sizes, further suggesting the detection is unlikely to be due to confusion.

ESO 547-012 Our radial velocity is consistent with the optical value of $V_{\rm h}=1992$ km s^-1 published in the ESO Catalogue (Lauberts & Valentijn 1988).

UGC 2728 An additional marginal feature is seen at $V_{\rm h}\sim906$ km s^-1, with $W_{20}\sim140$ km s^-1, and $S\sim0.84$ Jy km s^-1.

UGC 2731 Both UGC 2731 and its Sd neighbor UGC 2738 (FGC54A), $3\hbox{$.\mkern-4mu^\prime$ }7$ away, were within our beam. Both have nearly identical angular sizes, luminosities, and surface brightnesses. However, the two sources we detect in our beam have very different radial velocities, suggesting in fact that this galaxy pair is not physically associated.

FGC 436 Although the detection in our spectrum is somewhat marginal, its validity was reconfirmed by Giovanelli et al. (1997).

FGC 476 FGC 476 and FGC 477 cross one another in projection on the sky, although a physical association between these galaxies is unlikely given that neither disk appears optically disturbed and the optical counterparts have very different angular sizes. Our peculiar H I line profile is likely due to the detection of the line at the overlap region of two autocorrelator banks. The velocity width of the profile suggests that we have detected the Scd galaxy FGC 476 rather than the much smaller angular size galaxy FGC 477, which is a type Sd. We detected an additional marginal feature at $V_{\rm h}\sim1056$ km s^-1 with $W_{20}\sim321$ km s^-1 and $S\sim1.4$ Jy km s^-1 in our observations toward this position. Several uncatalogued dwarfs are also visible on the DSS in this region.

FGC 483 In addition to detecting FGC 483 at $V_{\rm h}=4966$ km s^-1 (see also Giovanelli et al. 1997), our spectrum shows three peculiar H I peaks between $V_{\rm h}=6000-7500$ km s^-1; the first has $V_{\rm h}\sim6408$ km s^-1, $W_{20}\sim106$ km s^-1, and $S\sim1.19$ Jy km s^-1, the second has $V_{\rm h}\sim6892$ km s^-1, $W_{20}\sim228$ km s^-1, and $S\sim1.27$ Jy km s^-1, and the third has $V_{\rm h}\sim7451$ km s^-1, $W_{20}\sim148$ km s^-1, and $S\sim1.04$ Jy km s^-1. No interference is evident in any of the individual scans. The morphology of the H I profiles is that of confusion with a group of objects lying partially outside the telescope beam, but no obvious optical counterparts are visible on the DSS.

FGCE 415 Our detected line profile may correspond to either FGCE 415 itself or to an uncatalogued dwarf galaxy visible on the DSS and lying within our beam.

FGC 495 The spirals MCG-01-12-037 ( $V_{\rm h}=4797$ km s^-1; Tsvetkov & Bartunov 1993) and NGC 1625 ( $V_{\rm h}=4759$ km s^-1; Theureau et al. 1998) lie $11\hbox{$.\mkern-4mu^\prime$ }1$ and $13\hbox{$.\mkern-4mu^\prime$ }9$, respectively, from FGC 495 and may have overlapped with our beam; however the double-horned morphology of our detected line profile and its comparatively lower systemic velocity ( $V_{\rm h}=4424$ km s^-1) suggest that our detection is probably not due to a confusion with either galaxy. FGC 495 is thus likely to be an outlier of the small, loose galaxy group containing both of these objects.

UGC 3172 Two sources were detected in our beam. That the second source corresponds to UGC 3172 is confirmed by Giovanelli et al. (1997). The other source has a dwarf-like line profile with $V_{\rm h}=1492$ km s^-1, W₂₀=140 km s^-1, and S=0.90 Jy km s^-1. We find no obvious optical counterpart for the second source on the DSS.

ESO 552-016 A second dwarf-like feature is also detected in our spectrum at $V_{\rm h}\sim1884$ km s^-1, with $W_{20}\sim146$ km s^-1, and $S\sim0.91$ Jy km s^-1. Several possible optical counterparts are visible on the DSS.

FGC 516 A second marginal detection is also present in the beam at $V_{\rm h}\sim2295$ km s^-1 with $W_{20}\sim235$ km s^-1 and $S\sim1.2$ Jy km s^-1.

FGC 517 Our line profile is broad and asymmetric and has the appearance of a confused source. However, no catalogued galaxy is known to lie at a similar redshift; the profile shape may result from a slight a telescope pointing offset.

FGC 524 Our observation was actually aimed at the target FGC 522, catalogued at $\alpha=05^{\rm h}03^{\rm m}52.5^{\rm s}$, $\delta=+85^{\circ}32'05''$ (B1950.0); however no object is visible at this position on the DSS or in a deeper R-band CCD image obtained with the WIYN telescope (Matthews et al., unpublished) and this object was subsequently excluded from the Revised FGC (Karachentsev et al. 1999). Therefore we believe our H I detection to correspond to FGC 524, which lies $5\hbox{$.\mkern-4mu^\prime$ }9$ from the reported position of FGC 522.

FGC 623 A second marginal source was present in our spectrum at $V_{\rm h}\sim1053$ km s^-1 with $W_{20}\sim219$ km s^-1 and $S\sim0.83$ Jy km s^-1.

FGC 654 Our H I detection of FGC 654 is extremely weak, but we see a similar features at the same radial velocity in two independent spectra taken with different autocorrelator configurations; in addition, the width and velocity of the measured H I line are in agreement with the optically-derived recessional and rotational velocities reported for FGC 654 by Makarov et al. (1999; $V_{\rm h}=5187$ km s^-1 & $V_{\rm max}=72$ km s^-1).

FGC 684 Our detection of this source is rather marginal, but its validity was reconfirmed by Giovanelli et al. (1997).

FGC 689 The second source in our spectrum at $V_{\rm h}=772$ km s^-1 appears to be the Im dwarf UGC 4117 (Schneider et al. 1990), $13\hbox{$.\mkern-4mu^\prime$ }3$ from FGC 689.

FGC 821 The nearly face-on Sbc spiral NGC 2721 with $V_{\rm h}=3712$ km s^-1, W₂₀=138 km s^-1 (Mathewson & Ford 1996) lies $3\hbox{$.\mkern-4mu^\prime$ }9$ from FGC 821, but based on the double-horned morphology of our detected line profile, its velocity offset from NGC 2721, and its broader linewidth, our detection of FGC 821 seems unlikely to be due to a confusion.

FGC 826 FGC 826 appears on the DSS as a dwarf-like object of extremely low surface brightness. We detect a second marginal feature in our spectrum with $V_{\rm h}\sim2458$ km s^-1, $W_{20}\sim72$ km s^-1, and $S\sim1.0$ Jy km s^-1.

FGCE 745 The highly peculiar H I profile we detect for FGCE 745 likely results from a blend with the E4 galaxy NGC 2865, $5\hbox{$.\mkern-4mu^\prime$ }7$ away, with an optical radial velocity of $V_{\rm h}=2611$ km s^-1 (de Vaucouleurs et al. 1991; hereafter RC3). Three H I detections have been reported for NGC 2865: based on Effelsberg observations, Huchtmeier (1994) reports $V_{\rm HI} = 2619$ km s^-1, W₂₀=502 km s^-1, and S=7.6 Jy km s^-1 while Huchtmeier (1997) reports $V_{\rm HI}=2850$ km s^-1, W₂₀=159 km s^-1, and S=1.7 Jy km s^-1; based on Green Bank 140-ft observations, Richter et al. (1994) find $V_{\rm HI}=2772$ km s^-1, W₂₀=164 km s^-1, and S=2.95 Jy km s^-1. A comparison with these 3 past observations suggests that the second portion of the H I line detected in our spectrum is due to a confusion with NGC 2865, while the first portion of the line corresponds to a detection of FGCE 745 itself. For the second feature we measure $V_{\rm h}=2766$ km s^-1, W₂₀=184 km s^-1, and $S\ge1.47$ Jy km s^-1. The presence of a highly flattened galaxy so near a large elliptical is surprising, although the DSS image of FGCE 745 shows hints of disturbance to its stellar disk.

UGC 5289 On the DSS, UGC 5289 is seen to be superposed on a diffuse, face-on spiral; this existence of this pair was noted in the UGC  catalogue, but was designated by a single UGC  number (Nilson 1973); a physical association between the galaxies is unlikely, but it is uncertain which of the two we have detected.

UGC 5301 The Sb spiral UGC 5295 is located $4\hbox{$.\mkern-4mu^\prime$ }8$ from UGC 5301 with $V_{\rm h}=4790$ km s^-1, W₂₀=307 km s^-1, and S=19.6 Jy km s^-1 (Haynes et al. 1988). However the velocity and linewidths measured for this target are consistent with the optical measurements of UGC 5301 obtained by Makarov et al. (1999) $V_{\rm h}=4873$ km s^-1 and $V_{\rm max}=118$ km s^-1, indicating that our H I profile is unlikely to be confused.

FGC 969 Although our detection is weak, its validity was reconfirmed by Giovanelli et al. (1997).

ESO 435-044 An additional narrow peak is visible in our spectrum near $V_{\rm h}\sim1219$ km s^-1. This may correspond to a detection of the dwarf ESO 435-045 located $7\hbox{$.\mkern-4mu^\prime$ }1$ from ESO 435-044 which has no previously reported redshift.

FGC 1028 Our detected H I feature is rather weak, but its velocity agrees with the optical redshift of $V_{\rm h}=3168$ km s^-1 reported for FGC 1028 by Makarov et al. (1999).

ESO 569-003 ESO 569-003 has an uncatalogued companion visible on the DSS, but our H I profile shows no evidence of a second source.

ESO 377-007 Both ESO 377-007 and the Sa-b spiral ESO 377-006 (redshift unknown), $3\hbox{$.\mkern-4mu^\prime$ }5$ away were contained in our beam, hence it is uncertain as to which galaxy we have detected.

FGC 1204 Several other catalogued galaxies without known redshifts are also present in this region, including the triple system CGCG 242-008, $8\hbox{$.\mkern-4mu^\prime$ }7$ from FGC 1204, making the source of our detected line profile uncertain.

FGC 1227 Our derived radial velocity for FGC 1227 is somewhat lower than the value of $V_{\rm h}=4777$ km s^-1 derived optically by Makarov et al. (1999).

UGC 6519 Our detection of UGC 6519 appears rather marginal, but its validity was reconfirmed by Giovanelli et al. (1997).

FGC 1282 Both FGC 1282 and the Sbc spiral NGC 3739, $5\hbox{$.\mkern-4mu^\prime$ }8$away were present in our beam, and neither has a published redshift. Based on our observed linewidths and integrated fluxes, we believe our lower velocity detection to correspond to FGC 1282 and our higher-velocity detection to NGC 3739. However, an additional uncatalogued galaxy was also present in our beam.

FGC 1348 Two spiral-like H I profiles are detected in our observations, although FGC 1348 has no companions visible on the DSS. We find no evidence of RFI in individual scans.

UGC A266 UGC A266 was included in our survey since it was listed in the LEDA database as an Im galaxy with an angular size of $6\hbox{$.\mkern-4mu^\prime$ }9$ $\times$ $0\hbox{$.\mkern-4mu^\prime$ }6$ (see also Nilson 1974) and therefore met our axial ratio selection criterion. However examination of the DSS and subsequent CCD imaging by Matthews et al. (unpublished) show that the only object near the catalogued position is an extremely diffuse irregular galaxy with an angular diameter of $\sim 1'$. It is displaced by roughly $27\hbox{$.\!\!^{\prime\prime}$ }5$ to the west and $31\hbox{$.\!\!^{\prime\prime}$ }6$ to the south of its original catalogued position of $\alpha = 11^{\rm h}59^{\rm m}54^{\rm s}, \delta=-14^{\circ}15'00''$ (B1950.0). The coordinates and optical diameter listed in Table 1 were measured from the R-band CCD image of Matthews et al. We measured a position angle of 155$^{\circ}$ for UGC A266 from this image. A faint, uncatalogued dwarf companion is also visible $\sim$ $3\hbox{$.\mkern-4mu^\prime$ }5$ away.

FGC 1394 UGC 7272 (FGC 1392) located $13\hbox{$.\mkern-4mu^\prime$ }2$away from FGC 1394 was also present in our beam, but it does not have a published redshift. Both it and FGC 1394 have similar apparent magnitudes, surface brightnesses and angular sizes; it is therefore uncertain which of these objects we have detected.

UGC 7844 A second marginal feature is seen in our spectrum with $V_{\rm h}\sim3662$ km s^-1, $W_{20}\sim311$ km s^-1, and $S\sim2.3$ Jy km s^-1.

FGC 1496 The second source detected in our spectrum at $V_{\rm h}=1443$ km s^-1 is likely to be DDO 142, an Sdm spiral $9\hbox{$.\mkern-4mu^\prime$ }2$ from FGC 1496 with a previously known redshift (Da Costa et al. 1998).

FGC 1519 The feature seen in our spectrum at $V_{\rm h}=1262$ km s^-1 appears to be due to NGC 4781, an Sd spiral $19\hbox{$.\mkern-4mu^\prime$ }4$ away (Richter & Huchtmeier 1987). An additional marginal feature is also seen near the edge of our bandpass with $V_{\rm h}\ge5261$ km s^-1, $W_{20}\ge102$ km s^-1 and $S\ge0.62$ Jy km s^-1.

FGC 1530 An optical redshift obtained by Grogin et al. (1998) confirms that the dwarf-like H I profile that we observe does indeed correspond to FGC 1530.

FGC 1633 The Sd spiral FGC 1635, $9\hbox{$.\mkern-4mu^\prime$ }3$ away (redshift unknown) may also have been present in our beam.

UGC 8590 Our detection of UGC 8590 appears marginal, but its validity was reconfirmed by Giovanelli et al. (1997).

UGC 9377 Our detection of UGC 9377 appears rather marginal, but the redshift of this galaxy was reconfirmed optically by Makarov et al. (1997a).

FGC 1845 MCG-02-38-030 (classified as an Sa spiral) is located only $2\hbox{$.\mkern-4mu^\prime$ }9$ from FGC1845, and has an optical redshift of $V_{\rm h}=2710$ km s^-1 (Da Costa et al. 1998). However, no H I detection has ever been reported for this source; moreover, an R-band CCD image (Matthews et al. unpublished) reveals that MCG-02-38-030 is actually an elliptical or S0, and hence it may be gas-poor. Because our detected line profile is double-horned, centered at a slightly lower velocity, and is of a width expected for an edge-on Sd galaxy, we believe our detection of FGC 1845 is real and not due to a confusion. Nonetheless, given the unperturbed optical morphology of FGC 1845, the proximity of these two objects is surprising.

FGC 1895 An additional marginal source was also detected in our spectrum near $V_{\rm h}\sim1967$ km s^-1 with $W_{20}\sim138$ km s^-1 and $S\sim0.64$ Jy km s^-1; this feature is possibly due to RFI.

FGC 1931 Makarov et al. (1999) reported an optically-derived recessional velocity for FGC 1931 of $V_{\rm h}=6089$ km s^-1.

UGC 10004 FGC 1947 may have overlapped in our beam. A second marginal feature at $V_{\rm h}\sim6994$ km s^-1 with $W_{20}\sim147$ km s^-1 and $S\sim0.77$ Jy km s^-1 was also detected.

UGC 10369 No obvious optical counterpart for the second source detected in our spectrum can be found on the DSS.

UGC 11243 The Sab spiral UGC 11246 is $4\hbox{$.\mkern-4mu^\prime$ }2$ from UGC 11243, at $V_{\rm h}=4071$ km s^-1 (Theureau et al. 1998). The line width and systemic velocity of our observed line profile suggest our detection is not due to a confusion, although the line profile may be partially blended. UGC 11243 thus appears to be part of a loose group of galaxies, together with UGC 11246 and NGC 6641.

FGC 2264 Our 3-peaked line profile may result from a blend between the peculiar ring galaxy MCG-02-50-008, ( $12\hbox{$.\mkern-4mu^\prime$ }8$ away, with an optical redshift of $V_{\rm h}=5996$ km s^-1, Fisher et al. 1995) and the H I emission from FGC2264 itself at a similar velocity. However, MCG-02-50-008 has no previously reported detection in H I.

FGC 2277 A second marginal feature was also detected in our spectrum with $V_{\rm h}\sim4170$ km s^-1, $W_{20}\sim85$ km s^-1, and $S\sim0.66$ Jy km s^-1. A possible uncatalogued dwarf counterpart is visible on the DSS.

FGC 2299 No obvious optical counterpart for the second detected H I source is visible on the DSS.

UGC 11666 UGC 11666 is actually a galaxy pair comprised of an edge-on Sdm galaxy and another spiral viewed close to face-on. The face-on system has an optically-derived radial velocity $V_{\rm h} = 9938$ km s^-1 (RC3), and we have detected this galaxy in our H I spectrum, near the edge of our bandpass; we measure $V_{\rm h}\approx\ 9935$ km s^-1, $W_{20}\approx$ 362 km s^-1, and $S~\rlap{$>$ }{\lower 1.0ex\hbox{$\sim$ }}\ 1.80$ Jy km s^-1. We believe the lower-velocity H I source we detected to correspond to the Sdm component of UGC 11666, making the UGC 11666 system physically unassociated.

FGC 2303 Our detected line profile has a surprisingly low redshift and narrow velocity width for this rather small angular size Sd. However, the DSS reveals no obvious candidates for interlopers.

ESO 342-017 Our H I detection appears marginal, but it corresponds closely with the optical recessional velocity $V_{\rm h}=7680$ km s^-1 reported for ESO 342-017 by Mathewson & Ford (1996).

FGC 2323 Although our line profile appears rather marginal, the validity of our detection was reconfirmed by Giovanelli et al. (1997).

ESO 467-063 An Irr galaxy ESO 467-062 is located $9\hbox{$.\mkern-4mu^\prime$ }6$from ESO 467-063, with an optical redshift of $V_{\rm h}$ = 4055 km s^-1 (Da Costa et al. 1998), although it should have been outside our beam. No detection of ESO 467-062 in H I has previously been reported, and our detection of ESO 467-063 shows no signature of confusion.

FGC 2468 No obvious optical counterpart for the second detected H I source is visible on the DSS.

FGC 2495 Giovanelli et al. (1997) report $V_{\rm h}$ =8272 km s^-1, W₂₀=379 km s^-1, and $S_{\rm cor}=$ 1.47 Jy km s^-1 for FGC 2495. We can identify no obvious cause for the discrepancy with our measured parameters from a comparison with their (unpublished) spectrum.

UGC 12659 Our detected line profile is peculiar and has the appearance of a blended detection, although the only optically identified galaxy in our beam was UGC 12656 with a previously known redshift of z=0.03440 (Huchra et al. 1999).

FGC 2548 A second feature appears in our spectrum near $V_{\rm h}=1069$ km s^-1; this is likely an artifact of structure in the bandpass (see Sect. 3.1.1) or interference.