The name
for each higher group in the classification of plants up to the order level is
derived from one of the genera it contains.
This genus is termed the type genus. Corylus
and a few related genera used to be classified in family Corylaceae but
have now been transferred to Betulaceae as subfamily Coryloideae. Corylus avellana (hazel) was first
named as such by Linnaeus in 1753. Corylus is the classical Latin name for the
hazel which has a distribution right across Europe and western Asia, except for
the far north and some islands. The
English names for the species include hazel, hazelnut and avelline. The first
recorded use of the species name was by Pliny the Elder in his Naturalis
Historia, from Avella, a town in Italy.
It was later used by Leonhart Fuchs in his De historia stirpium commentarii insignes (1542) in which he uses
the name Avellana nux sylvestris (the wild nut of Avella).
The text
from Linnaeus (1753) is as follows:
The male flowers of the hazel are a
conspicuous feature of the countryside from late December onwards. They are borne on long thin catkins; because
they bear male flowers only they are termed staminate
catkins. These have a short stalk
and then a central rachis to which the individual flowers are attached spirally. Each flower has a hooded pale creamy-green bract with the stamens underneath. The bract is pointed in the middle and is
fringed with short, pale, curly hairs.
With magnification it can be seen that there are two further structures
under the bracts – these are the bracteoles and
they are attached to the outer half of the bracts; they are also fringed with
curly hairs. The stamens are attached to
the underside of the bract at about the same point as the bracteoles. The bracts taper to the rachis so it is
difficult to decide whether the whole catkin is a raceme (each flower with a
stalk) or a spike (each without a stalk).
There are six stamens in the upper part of the bract and two arising
from the narrowed part of the bract, nearer its point of attachment to the
rachis. The six upper stamens form three
pairs and one or more of these may have their filaments joined near the
base. In all the flowers inspected the
basal pair of stamens have their filaments joined.
The number of flowers under each bracts as well as the number of
The female flowers are inside a bud-like
structures which are further back on the branches than the male ones. The bud scales towards the base are green and
fringed with pale hairs. The length of
the fringe hairs is longer on the scales further inside and these also have an
increasing amount of silvery hair on their outer surface. From the tip of the bud there are a number of
stigmas. Early on these are bright red
and then they fade to a purple-brown. On
the ones I inspected there were 18-20 stigmas.
Hayward (1987) in his New Key to Wild Flowers, page 138 wrongly states “the
female flowers look like tiny buds with 2 red styles”
If the outer scales are
removed, a central section is isolated, consisting of narrow hairy bracts and
the stigmas. If prised apart and
carefully examined the stigmas are in pairs and each bract has two pairs of
stigmas associated with it and a pair of smaller unequally-sized
bracteoles. It is very difficult to see
this as the flowers are so closely associated.
If the bracteoles have dried a bit, some can be seen as having an uneven
outline as two triangular lobes. At the
base of the stigmas is a small ovary which is divided into two ovules. Each flower therefore has four stigmas (two
per ovule) and thus the whole structure contains five flowers (= 20 stigmas). There is no clear distinction between stigma
and style. The surface of the style is
minutely papillose (uneven with microscopic rounded bumps). The Flora of China (1999) volume 4 interprets
the structures as each ovule having a single style which is divided to the
base.
The Flora
Europaea makes reference to a small irregularly-lobed perianth in addition to
the bracts and bracteoles as does Stace (2011) but I could see no further
structures apart from the silky hairs on top of the ovary.
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