Galanthus

General

All species of Galanthus are perennial petaloid herbaceous bulbous (growing from bulbs) monocot plants. The genus is characterised by the presence of two leaves, pendulous white flowers with six free perianth segments in two whorls. The inner whorl is smaller than the outer whorl and has green markings.^[3]

Vegetative

Leaves

These are basal, emerging from the bulb initially enclosed in a tubular membranous sheath of cataphylls. Generally, these are two (sometimes three) in number and linear, strap-shaped, or oblanceolate. Vernation, the arrangement of the emerging leaves relative to each other, varies among species. These may be applanate (flat), supervolute (conduplicate), or explicative (pleated). In applanate vernation, the two leaf blades are pressed flat to each other within the bud and as they emerge; explicative leaves are also pressed flat against each other, but the edges of the leaves are folded back (externally recurved) or sometimes rolled; in supervolute plants, one leaf is tightly clasped around the other within the bud and generally remains at the point where the leaves emerge from the soil^[4] (for illustration, see Stearn^[5] and Davis^[6]). In the past, this feature has been used to distinguish between species and to determine the parentage of hybrids, but now has been shown to be homoplasious, and not useful in this regard.

The scape (flowering stalk) is erect, leafless, terete, or compressed.^[7]

Reproductive

Inflorescence

At the top of the scape is a pair of bract-like spathes (valves) usually fused down one side and joined by a papery membrane, appearing monophyllous (single). From between the spathes emerges a solitary (rarely two), pendulous, nodding, bell-shaped white flower, held on a slender pedicel. The flower bears six free perianth segments (tepals) rather than true petals, arranged in two whorls of three, the outer whorl being larger and more convex than the inner whorl. The outer tepals are acute to more or less obtuse, spathulate or oblanceolate to narrowly obovate or linear, shortly clawed, and erect spreading. The inner tepals are much shorter (half to two thirds as long), oblong, spathulate or oblanceolate, somewhat unguiculate (claw like); tapering to the base and erect. These tepals also bear green markings at the base, the apex, or both, that when at the apex, are bridge-shaped over the small sinus (notch) at the tip of each tepal, which are emarginate. Occasionally, the markings are either green-yellow, yellow, or absent, and the shape and size varies by species.^[8][7]

Androecium

The six stamens are inserted at the base of the perianth, and are very short (shorter than the inner perianth segments), the anthers basifixed (attached at their bases) with filaments much shorter than the anthers; they dehisce (open) by terminal pores or short slits.^[7]

Gynoecium, fruit and seeds

The inferior ovary is three-celled. The style is slender and longer than the anthers; the stigma is minutely capitate. The ovary ripens into a three-celled capsule fruit. This fruit is fleshy, ellipsoid or almost spherical, opening by three flaps, with seeds that are light brown to white and oblong with a small appendage or tail (elaiosome) containing substances attractive to ants, which distribute the seeds.^[7][9]

The chromosome number is 2n=24.^[10][8]

Floral formula: ${\displaystyle \star \;P_{3+3}\;A_{3+3}\;G_{\overline {(3)}}}$

History

Early

Snowdrops have been known since early times, being described by the classical Greek author Theophrastus, in the fourth century BCE, in his Περὶ φυτῶν ἱστορία (Latin: Historia plantarum, Enquiry into plants). He gave it, and similar plants, the name λευκόἲον (λευκος, leukos "white" and ἰόν, ion "violet") from which the later name Leucojum was derived. He described the plant as "ἑπεἰ τοῖς γε χρώμασι λευκἂ καἱ οὐ λεπυριώδη" (in colour white and bulbs without scales)^[16] and of their habits "Ἰῶν δ' ἁνθῶν τὀ μἑν πρῶτον ἑκφαἱνεται τὁ λευκόἲον, ὅπου μἑν ό ἀἠρ μαλακώτερος εὐθὑς τοῦ χειμῶνος, ὅπου δἐ σκληρότερος ὕστερον, ἑνιαχοῡ τοῡ ἣρος" (Of the flowers, the first to appear is the white violet. Where the climate is mild, it appears with the first sign of winter, but in more severe climates, later in spring)^[17]

Rembert Dodoens, a Flemish botanist, described and illustrated this plant in 1583 as did Gerard in England in 1597 (probably using much of Dodoens' material), calling it Leucojum bulbosum praecox (Early bulbous violet). Gerard refers to Theophrastus's description as Viola alba or Viola bulbosa, using Pliny's translation, and comments that the plant had originated in Italy and had "taken possession" in England "many years past".^[18] The genus was formally named Galanthus and described by Carl Linnaeus in 1753,^[19] with the single species, Galanthus nivalis, which is the type species. Consequently, Linnaeus is granted the botanical authority. In doing so, he distinguished this genus and species from Leucojum (Leucojum bulbosum trifolium minus), a name by which it previously had been known.^[2][20][21]

Phylogeny

Galanthus is one of three closely related genera making up the tribe Galantheae within subfamily Amaryllidoideae (family Amaryllidaceae). Sometimes snowdrops are confused with the other two genera, Leucojum and Acis (both called snowflakes). Leucojum species are much larger and flower in spring (or early summer, depending on the species), with all six tepals in the flower being the same size, although some "poculiform" (goblet- or cup-shaped) Galanthus species may have inner segments similar in shape and length to the outer ones. Galantheae are likely to have arisen in the Caucusus.^[39]

Subdivision

Galanthus has approximately 20 species, but new species continue to be described.^[2] G. trojanus was identified in Turkey in 2001.^[40][41] G. panjutinii (Panjutin's snowdrop)^[42] was discovered in 2012 in five locations in a small area (estimated at 20 km² (7.7 sq mi)) of the northern Colchis area (western Transcaucasus) of Georgia and Russia.^[43][44] G. samothracicus was identified in Greece in 2014. Since it has not been subjected to genetic sequencing, it remains unplaced. It resembles G. nivalis, but is outside the distribution of that species.^[45][46]

Many species are difficult to identify, however, and traditional infrageneric classification based on plant morphology alone, such as those of Stern (1956),^[47] Traub (1963)^[48] and Davis^[49] (1999, 2001),^[50][51][7] has not reflected what is known about its evolutionary history, due to the morphological similarities among the species and relative lack of easily discernible distinguishing characteristics.^[52][53][54] Stern divided the genus into three series according to leaf vernation (the way the leaves are folded in the bud, when viewed in transverse section, see Description);^[47]

• section Nivales Beck (flat leaves)
• section Plicati Beck (plicate leaves)
• section Latifolii Stern (convolute leaves)

Stern further utilised characteristics such as the markings of the inner segments, length of the pedicels in relation to the spathe, and the colour and shape of the leaves in identifying and classifying species

Traub considered them as subgenera;

• subgenus Galanthus
• subgenus Plicatanthus Traub & Moldk.
• subgenus Platyphyllanthe Traub

By contrast Davis, with much more information and specimens, included biogeography in addition to vernation, forming two series. He used somewhat different terminology for vernation, namely applanate (flat), explicative (plicate), and supervolute (convolute). He merged Nivalis and Plicati into series Galanthus, and divided Latifolii into two subseries, Glaucaefolii (Kem.-Nath) A.P.Davis and Viridifolii (Kem.-Nath) A.P.Davis.^[50]

Early molecular phylogenetic studies confirmed the genus was monophyletic and suggested four clades, which were labelled as series, and showed that Davis' subseries were not monophyletic.^[53][54] An expanded study in 2013 demonstrated seven major clades, corresponding to biogeographical distribution. This study used nuclear encoded nrITS (Nuclear ribosomal internal transcribed spacer), and plastid encoded genes matK (Maturase K), trnL-F, ndhF, and psbK–psbI, and examined all species recognised at the time, as well as two naturally occurring putative hybrids. The morphological characteristic of vernation that earlier authors had mainly relied on was shown to be highly homoplasious. A number of species, such as G. nivalis and G. elwesii demonstrated intraspecific biogeographical clades, indicating problems with speciation and there may be a need for recircumscription. These clades were assigned names, partly according to Davis' previous groupings. In this model clade, the group containing G. platyphyllus is sister to the rest of the genus.^[3]

By contrast, another study performed at the same time, using both nuclear and chloroplast DNA, but limited to the 14 species found in Turkey, largely confirmed Davis' series and subseries, and with biogeographical correlation. Series Galanthus in this study corresponded to clade nivalis, subseries Glaucaefolii with clade Elwesii and subseries Viridifolii with clades Woronowii and Alpinus. However, the model did not provide complete resolution.^[55]

Etymology

Galanthus is derived from the Greek γάλα (gala), meaning "milk" and ἄνθος (anthos) meaning "flower", alluding to the colour of the flowers. The epithet nivalis is derived from the Latin, meaning "of the snow".^[57][58] The word "Snowdrop" may be derived from the German Schneetropfen (snow-drop), the tear drop shaped pearl earrings popular in the sixteenth and seventeenth centuries. Other, earlier, common names include Candlemas bells, Fair maids of February, and White ladies (see Symbols).^[21]

Snowdrop gardens

Celebrated as a sign of spring, snowdrops may form impressive carpets of white in areas where they are native or have been naturalised. These displays may attract large numbers of sightseers.^[59] There are a number of snowdrop gardens in England, Wales, Scotland, and Ireland.^[67] Several gardens open specially in February for visitors to admire the flowers. Sixty gardens took part in Scotland's first Snowdrop Festival (1 Feb–11 March 2007).^[68] Several gardens in England open during snowdrop season for the National Gardens Scheme (NGS) and in Scotland for Scotland's Gardens. Colesbourne Park in Gloucestershire is one of the best known of the English snowdrop gardens, being the home of Henry John Elwes, a collector of Galanthus specimens, and after whom Galanthus elwesii is named.^[69][70]

Cultivars

Numerous single- and double-flowered cultivars of Galanthus nivalis are known, and also of several other Galanthus species, particularly G. plicatus and G. elwesii. Also, many hybrids between these and other species exist (more than 500 cultivars are described in Bishop, Davis, and Grimshaw's book, plus lists of many cultivars that have now been lost, and others not seen by the authors). They differ particularly in the size, shape, and markings of the flower, the period of flowering, and other characteristics, mainly of interest to the keen (even fanatical) snowdrop collectors, known as "galanthophiles", who hold meetings where the scarcer cultivars change hands.^[71]  Double-flowered cultivars and forms, such as the extremely common Galanthus nivalis f. pleniflorus 'Flore Pleno', may be less attractive to some people, but they can have greater visual impact in a garden setting. Cultivars with yellow markings and ovaries rather than the usual green are also grown, such as 'Wendy's Gold'.^[72] Many hybrids have also occurred in cultivation.^[7]

Awards

As of July 2017^[update], the following have gained the Royal Horticultural Society's Award of Garden Merit:^[73]

Propagation

Propagation is by offset bulbs, either by careful division of clumps in full growth ("in the green"), or removed when the plants are dormant, immediately after the leaves have withered; or by seeds sown either when ripe, or in spring. Professional growers and keen amateurs also use such methods as "twin-scaling" to increase the stock of choice cultivars quickly.

Symbolism

Early names refer to the association with the religious feast of Candlemas (February 2) – the optimum flowering time of the plant – at which young women, robed in white, would walk in solemn procession in commemoration of the Purification of the Virgin, an alternative name for the feast day. The French name of violette de la chandaleur refers to Candlemas, while an Italian name, fiore della purificazione, refers to purification. The German name of Schneeglöckchen (little snow bells) invokes the symbol of bells.^[21][59]

In the language of flowers, the snowdrop is synonymous with 'hope' (and the goddess Persephone's/Proserpina's return from Hades), as it blooms in early springtime, just before the vernal equinox, and so, is seen as 'heralding' the new spring and new year.

In more recent times, the snowdrop was adopted as a symbol of sorrow and of hope following the Dunblane massacre in Scotland, and lent its name to the subsequent campaign to restrict the legal ownership of handguns in the UK.^[108][109]