Based on a recessional velocity of 2020 km/sec, NGC 4250 is about 95 million light years away. Given that and its apparent size of 2.0 by 1.1 arcmin, it is about 55 thousand light years across. Its core is unusually bright compared to its disc, so it may be a starburst galaxy.

Apparent size 3.6 by 1.5 arcmin.

Apparent size 1.3 by 0.3 arcmin. Listed as a member (VCC 289) of the Virgo Cluster.

Apparent size 0.9 by 0.8 arcmin. A Seyfert galaxy (type Sy 1).

Historical Identification: Per Dreyer, NGC 4254 (= GC 2838 = JH 1173, Méchain, M99, 1860 RA 12 11 43, NPD 74 48.2) is "a very remarkable object (per William and John Herschel), bright, large, round, gradually brighter middle, mottled but not resolved, (per the 3rd Lord Rosse and Lassell), 3 branched spiral". The position precesses to RA 12 18 50.0, Dec +14 25 08, almost dead center on the galaxy listed above and the description fits, so the identification is certain.
Note About Spiral Structure: Per Gottlieb, Lord Rosse's observation was the second "confirmed" spiral structure (M51 being the first), and his assistant (Rambaut) later wrote a detailed description of the spiral structure. Dreyer's also crediting Lassell for observing the spiral structure was based on a sketch showing three principal arms and one or two offshoots; Lassell also noted "The spiral form is very evident, more so, I think than in any other nebula I have seen."
 The earliest published reference to this object's spiral nature is in Lord Rosse's 1850 paper Observations on the Nebulae (see PW1850 Parsons, William in Historical References), which includes a sketch of the "nebula" (plate XXXV, Fig.2) drawn by Lord Rosse. The detailed list of observations of M99 in that paper lists Rambaut's observation of 1848, but no earlier observation. However, there is a sort of off-hand mention of the spiral structure being noticed in the spring of the year following the discovery of M51's spiral structure, which would correspond to the observation of April, 1846. And although most of the 3rd Lord Rosse's discoveries were actually made by his assistants, he must have done that observation himself, as during the worst years of the Great Famine (Birr Castle is in Ireland), he temporarily worked without assistants.
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 2735 km/sec (and H₀ = 70 km/sec/Mpc), NGC 4254 is about 125 to 130 million light-years away, in total disagreement with redshift-independent distance estimates of about 40 to 65 million light-years (an HST press release uses a distance of about 50 million light years, which is the distance to the center of the Virgo Cluster (the galaxy is listed as a member, VCC 307, of the Cluster). In most cases, such a discrepancy would mean that the galaxy is actually much further away than the Cluster it supposedly belongs to. However, in rich, massive clusters of galaxies, as galaxies move through the cluster they can be greatly affected by the cluster's gravity, and in the case of the Virgo Cluster, "peculiar velocities", or motions relative to neighboring galaxies that have nothing to do with the Universal Expansion, can be surprisingly large. So it appears that in the case of M99, it is in the Virgo Cluster, but as it passes through the region near the center of the cluster, only about 1100 km/sec of its recessional velocity is due to the expansion of the space between us and the cluster, and over 1600 km/sec is due to the gravity of the cluster. Once the galaxy has passed through the region near the center of the cluster its gravity will start slowing it down, and it will eventually cease its outward motion relative to the rest of the cluster, fall back toward the center, and by the time it nears the center of the cluster again it should actually have a negative recessional velocity, which is usually observed only for galaxies in our immediate neighborhood.
 Taking all that into account and assuming a distance of around 50 million light-years, NGC 4254's apparent size of about 5.35 by 4.2 arcmin (from the images below) implies that the galaxy is about 75 to 80 thousand light-years across. The galaxy has a strong emission line spectrum, caused by interstellar gases being heated by hot, bright young stars in its numerous recently formed clusters.
Use By The de Vaucouleurs Atlas: NGC 4254 is used by the de Vaucouleurs Atlas of Galaxies as an example of type SA(s)c. However, in the Spitzer Survey of Stellar Structure in Galaxies (a 2015 extension of the de Vaucouleurs classification system) it is listed as type SA(s)c pec, whence the type shown in the description line.

Historical Identification:
Discovery Notes: Voigt's discovery was one of ten nebulae he discovered between March and August of 1865; but they were only noted in his observing records, and were not published until 1987, so Dreyer had no knowledge of his observation.
Physical Information: Apparent size 1.3 by 0.5 arcmin. Listed as a member (VCC 312) of the Virgo Cluster.

Apparent size 4.5 by 0.8 arcmin.

Apparent size 1.5 by 0.5 arcmin? Listed as a member (VCC 323) of the Virgo Cluster.

Historical Identification: Per Dreyer, NGC 4258 (= GC 2841 = JH 1175 = WH V 43, 1860 RA 12 12 02, NPD 41 55.1) is "very bright, very large, very much extended 0°, suddenly brighter middle and bright nucleus". The position precesses to RA 12 18 58.4, Dec +47 18 14, right on the galaxy listed above and the description, though not exact, is reasonable; so the identification is certain.
Additional Notes (about its listing as M106): Although Méchain discovered the nebula and estimated its position in 1781, his discovery came after Messier submitted his Catalog for publication, and with no immediate deadline for determining an exact position, as of the date of Méchain's letter of May 6, 1783 to Bernoulli he had still not gotten around to it. Perhaps the nebula would have been added to a later edition of Messier's Catalog, but none was ever published, and neither John Herschel (when he compiled his General Catalog) nor Dreyer (when he compiled his New General Catalog) appears to have been aware of Méchain's observation, for if they had been aware of it his name would almost certainly have been added to Dreyer's entry for NGC 4258. However, given the relatively early date of Méchain's discovery, when Helen Sawyer Hogg decided to add NGC 3379 to Messier's Catalog as M105, she also added NGC 4258 as M106 and NGC 6171 as M107.
Physical Information: Apparent size 18.6 by 7.2 arcmin?

Below, a multispectral false-color image of NGC 4258 shows "anomalous" spiral arms with no counterpart in the visible spectrum, thought to be due to material being pulled into a black hole at the center of the galaxy, and subsequent emission of material at very high velocity. X-rays are shown in blue, visible light in yellow, infrared radiation in red, and radio emissions in purple. (Image Credit X-ray: NASA/CXC/Univ. of Maryland/A.S. Wilson et al.; Optical: Palomar Observatory. DSS; IR:JPL-Caltech; VLA: NRAO/AUI/NSF/NASA)

Apparent size 1.1 by 0.4 arcmin. Listed as a member (VCC 342) of the Virgo Cluster.

Apparent size 2.7 by 1.3 arcmin. Listed as a member (VCC 341) of the Virgo Cluster.

Apparent size 5.5 by 3.5 arcmin. Listed as a member (VCC 345) of the Virgo Cluster.

Apparent size 1.8 by 1.6 arcmin. Listed as a member (VCC 355) of the Virgo Cluster.

Per Dreyer, NGC 4263 (GC 2846 = WH III 535, 1860 RA 12 12 26, NPD 101 28.5) is "very faint, pretty large, irregular figure". The second IC notes "4263 no doubt = 4265. Howe saw only one". The position precesses to RA 12 19 39.0, Dec -12 15 10, less than 2 arcmin southwest of the galaxy, and there is nothing else nearby, so the identification is certain. (See NGC 4265 for a discussion of the double listing.) Apparent size 1.2 by 0.6 arcmin.

Apparent size 0.9 by 0.7 arcmin. Listed as a member (VCC 358) of the Virgo Cluster.

Per Dreyer, NGC 4265 (Swift list III (#63), 1860 RA 12 12 28, NPD 101 28.8) is "very faint, pretty small, round". The second IC notes "4263 no doubt = 4265. Howe saw only one". The position precesses to RA 12 19 41.0, Dec -12 15 28, a little over 2 arcmin south of the galaxy, and there is nothing else nearby, so the identification is certain. The only problem is the duplicate listing, which is a bit odd, as Swift's position is nearly identical to Herschel's, so he should have realized he was looking at the same object. But for whatever reason he didn't (see the note at the end of this entry), so Dreyer assumed there were two nebulae in the region and dutifully created two entries. It was only after Howe stated that he could only find one nebula in the area that Dreyer realized the two entries must be the same. Normal practice is to call duplicate listings by the name corresponding to the earlier observation, so the galaxy is usually called NGC 4263 (which see for anything else); but Dreyer suggested using NGC 4265 instead, so there may be some places where the object is listed as the later entry. (Note: Per Corwin, Swift may have ignored Herschel's observation because the notes for John Herschel's GC state that his father was unable to find the object in a subsequent effort to observe it, and suggested that it might have been a comet.)

Apparent size 1.8 by 0.4 arcmin. Listed as a member (VCC 362) of the Virgo Cluster.

Apparent size 3.0 by 2.8 arcmin. Listed as a member (VCC 369) of the Virgo Cluster.

Apparent size 1.4 by 0.6 arcmin. Listed as a member (VCC 371) of the Virgo Cluster.

Apparent size 1.3 by 0.8 arcmin. Listed as a member (VCC 373) of the Virgo Cluster.

Apparent size 2.0 by 0.9 arcmin. Listed as a member (VCC 375) of the Virgo Cluster.

Apparent size 1.5 by 1.3 arcmin.

Apparent size 1.7 by 1.3 arcmin.

Apparent size 2.3 by 1.5 arcmin. Listed as a member (VCC 382) of the Virgo Cluster.

Apparent size 6.8 by 2.4 arcmin.

Apparent size 1.1 by 1.0 arcmin.

Apparent size 1.6 by 1.4 arcmin. Listed as a member (VCC 393) of the Virgo Cluster.

Apparent size 1.1 by 0.8 arcmin. Listed as a member (VCC 386) of the Virgo Cluster.

Apparent size 4.1 by 3.8 arcmin. A Seyfert galaxy (type Sy 1).

Per Dreyer, NGC 4279 (Swift list III (#64), 1860 RA 12 13 08, NPD 100 55.7) is "most extremely faint, very small, round". The second IC adds "not found by Howe (2 nights)". The position precesses to RA 12 20 21.0, Dec -11 42 21, almost 3 arcmin south-southwest of the nearest nebula, so it isn't surprising that Howe didn't find it; but there isn't anything else nearly as close to Swift's position as the galaxy listed above, so its identity is considered reasonably certain (but see NGC 4280 for more about identifications in this region). Apparent size 1.1 by 0.7 arcmin.

Per Dreyer, NGC 4280 (Swift list III (#65), 1860 RA 12 13 13, NPD 100 55.2) is "most extremely faint, very small, round". The second IC adds "4285 is fainter than 4280 (Howe, 2 nights)". The position precesses to RA 12 20 26.0, Dec -11 41 51, but there is nothing there. However, given the wide-field image below and the IC notes for NGC 4279, 4280 and 4285 we can surmise what happened when Howe observed the area. Instead of the three objects (III-64, III-65 and III-66) recorded by Swift and listed by Dreyer as the corresponding NGC objects, he found only two nebulae, one of which was at almost the same position given by Swift (III-66 = NGC 4285), but the other well to the north of Swift's other positions. Seeing nothing but some faint stars between the two nebulae, he assumed that the western galaxy was Swift's III-65, and Swift's III-64 was an unobservable object to the west of that. Hence the IC note for NGC 4279 stating that Howe could not find it, and the ones for NGC 4280 and 4285 stating that the western galaxy was the brighter one. If that interpretation were correct, then NGC 4279 would be "lost or nonexistent", the western galaxy would be NGC 4280, and the eastern would be NGC 4285 (which is the only certainty here, since it is the only one of Swift's three positions that is reasonably accurate). However, current thinking is that the western galaxy is Swift's III-64 (and therefore NGC 4279), the eastern is his III-66 (and therefore NGC 4285), and something between the two is Swift's III-65 (and therefore NGC 4280). But there is nothing between the two galaxies save for the three faint stars listed above, so that is the current identification of NGC 4280. (Looking at the image below, it seems obvious that either III-64 or III-65 could be assigned to the western galaxy, making it either NGC 4279 or 4280, so whether Howe's identifications or the current ones are correct cannot be decided with certainty; hence my decision to state the identities for the two entries as "probably" the currently accepted ones.)

Apparent size 3.0 by 1.6 arcmin. Listed as a member (VCC 408) of the Virgo Cluster.

Apparent size 1.2 by 0.6 arcmin. Listed as a member (VCC 411) of the Virgo Cluster.

Apparent size 1.5 by 1.5 arcmin.

Apparent size 2.2 by 1.0 arcmin.

Per Dreyer, NGC 4285 (Swift list III (#66), 1860 RA 12 13 28, NPD 100 52.2) is "extremely faint, pretty small, round". This is the third of three objects recorded by Swift on the same night, the first two of which are listed as being "most extremely faint", and therefore fainter than the third. The second IC notes "4285 is fainter than 4280 (Howe, 2 nights)", indicating that one of the preceding objects is actually brighter (though what it should be called is uncertain, as discussed at the entry for NGC 4280). The position precesses to RA 12 20 41.0, Dec -11 38 51, less than half an arcmin southeast of the galaxy, so the identification is certain. Apparent size 0.9 by 0.5 arcmin.

Apparent size 1.5 by 0.8 arcmin. (See IC 3181 for a brief discussion of the duplicate listing.)

Apparent size 1.2 by 0.2 arcmin. Listed as a member (VCC 434) of the Virgo Cluster.

Apparent size 2.2 by 1.6 arcmin.

Apparent size 0.4 by 0.4 arcmin.

Apparent size 3.9 by 0.4 arcmin. Listed as a member (VCC 449) of the Virgo Cluster.

Apparent size 2.2 by 1.6 arcmin.

Apparent size 2.0 by 1.7 arcmin.

Vr 2260 km/sec. Apparent size 1.6 by 1.2 arcmin. Listed as a member (VCC 462) of the Virgo Cluster.

Apparent size 0.45 by 0.35 arcmin. Apparently nothing else available. Since the recessional velocity and distance are unknown, whether PGC 213977 shares anything with NGC 4292 other than being in a similar direction is also unknown. However, the galaxy appears to be a more or less normal spiral, and if so its small apparent size implies that it is much further away than its apparent neighbor.

Per Dreyer, NGC 4293 (= John Herschel's GC 2867, 1860 RA 12 14 08, NPD 70 50.5) is "faint, very large, extended, little brighter middle, mottled but not resolved". The position precesses to RA 12 21 13.4, Dec +18 22 52, within 0.2 arcmin of the center of the galaxy, so the identification is certain. Based on a recessional velocity of 895 km/sec, NGC 4293 is about 40 million light years away, in good agreement with redshift-independent distance estimates of 27 to 55 million light years. Given that and its apparent size of 5.6 by 2.6 arcmin, it is about 70 thousand light years across. Listed as a member (VCC 460) of the Virgo Cluster.

Apparent size 3.2 by 1.2 arcmin. Listed as a member (VCC 465) of the Virgo Cluster.

Apparent size 0.9 by 0.6 arcmin.

Per Dreyer, NGC 4296 (GC 2872 = WH III 92, 1860 RA 12 14 23, NPD 82 34.0) is "very faint, very small". The position precesses to RA 12 21 31.5, Dec +06 39 22, just off the eastern edge of the galaxy in question, so the identification is certain. (As discussed at the entry for NGC 4297 (which see), a comparison of Dreyer's entries for NGC 4296 and 4297 implies that the latter galaxy must be a fainter companion of NGC 4296.) Apparent size 1.4 by 0.9 arcmin. Listed as a member (VCC 475) of the Virgo Cluster.

Per Dreyer, NGC 4297 (GC 2873 = WH III 93, 1860 RA 12 14 24, NPD 82 34.0) is "extremely faint, extremely small, (not found by d'Arrest)". (It is important to note that NGC 4296 (which see for images) and 4297 have nearly identical entries, the only difference being that 4297 is listed as being 1 minute of time to the east, and noticeably fainter. So if 4297 exists, it must be a galaxy very close to 4296, and somewhat fainter.) The position precesses to RA 12 21 32.5, Dec +06 39 22, which is a minute to the east of NGC 4296, but there is nothing there, so it is hardly surprising that d'Arrest couldn't find the supposed companion. As it turns out, the problem is caused by Dreyer's entry, not Herschel's observations. Herschel's entries for III-92 (NGC 4296) and III-93 (NGC 4297) list a single position for the pair, stating only that the fainter galaxy is "close by" the brighter one. Similarly, John Herschel's entries for GC 2872 (NGC 4296) and 2873 (NGC 4297) list exactly the same position (though without the note "close by", which perhaps seemed obvious given the identical position). It was only in the NGC that III-93 acquired an RA 1 minute larger, thereby putting it east of the larger galaxy. If we ignore the unexplained change in position and simply look for something "close by" NGC 4296, we find a perfectly suitable candidate just to the northwest of that galaxy, and it seems certain that it must be what Herschel recorded as III-93, so the identification of NGC 4297 with that galaxy is equally certain. Apparent size 0.5 by 0.2 arcmin. Listed as a member (VCC 473) of the Virgo Cluster.

Historical Identification: Per Dreyer, NGC 4298 (= GC 2874 = JH 1198 = WH II 111, 1860 RA 12 14 25, NPD 74 36.9) is "faint, large, extended, very gradually brighter middle, western of 2", the other being NGC 4302. The position precesses to RA 12 21 31.4, Dec +14 36 28, within the northwestern outline of the galaxy listed above, and the description is a perfect fit (including the reference to the other galaxy), so the identification is certain.
Physical Information: Based on a recessional velocity of 1135 km/sec (and H₀ = 70 km/sec/Mpc), NGC 4298 is about 50 to 55 million light years away, in good agreement with redshift-independent distance estimates of about 45 to 70 million light years (the HST news release uses 55 million light years as the approximate distance of the pair of galaxies). Given that and its apparent size of about 2.8 by 1.7 arcmin (from the images below), it is about 40 to 45 thousand light years across (the HST news release uses 45 thousand light years). NGC 4298 is listed as a member (VCC 483) of the Virgo Cluster, and both it and its apparent companion are at an apparently appropriate distance for being members of that Cluster. However, although very close in their field of view, there is no obvious interaction between them, so they are probably separated by a couple of million light years or more (as an example, the Milky Way and Andromeda galaxies are only a couple of million light years apart, but that is far enough that there is no obvious interaction between them).

Apparent size 1.7 by 1.6 arcmin. Listed as a member (VCC 491) of the Virgo Cluster.

Based on a recessional velocity of 45725 km/sec, a straightforward calculation indicates that PGC 169102 is about 2130 million light years away. However, for objects at such distances we should take into account the Universal expansion during the time it took their light to reach us. Doing that shows that the galaxy was about 1790 million light years away at the time the light by which we see it was emitted, about 1920 million years ago (the difference between the two values being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of 0.45 by 0.15 arcmin (including its peculiar northern extension), the galaxy and its northern extension span about 235 thousand light years.