CHAPTER VI

THE MALE FERN AND ITS RELATIVES

Apart from the Bracken Fern which, as we have seen, is abundant almost everywhere, there are few ferns more common than certain of the leading members of the sub-order Aspidieæ. The British representatives of this sub-order include the important genus _Nephrodium_, of which the Male Fern is the leading example. In addition we have the Shield Ferns (_Aspidium_), and also some interesting species gathered together under the genera _Woodsia_ and _Cystopteris_.

_Nephrodium Filix-mas._ The generic name is derived from the Greek _nephros_, “a kidney,” this having reference to the kidney-shaped indusia which is typical of the genus; _Filix-mas_, of course, is a name formed of two Latin words, _filix_, “a fern,” and _mas_, “a male.” In some books the species is called _Lastrea Filix-mas_, and _Aspidium Filix-mas_. The Male Fern.

One is almost tempted to follow the example of the early writers of botanical works and to say that the plant is so well known that “it needeth no description.” However, such a fine Fern, common though it be, is certainly as worthy of a notice as any species within the covers of this book. A very characteristic feature of the Male Fern is its stout and sometimes very upright stem or caudex. In some plants this is at times so large that it almost resembles a short trunk. It will readily be seen that the leaves arise from the outside of the crown of the plant, whilst at the base of the stalks occur the fibrous roots. Within the circle of the developed leaves we may find the immature fronds; the least advanced of these may not develop for three years. The crown of the plant, as well as the stipes and the rachis, are more or less covered with brown scales. The length of the fronds of the Male Fern vary enormously. In a favourable situation the leaves may measure as much as three feet or more, though an average example would be a good deal less than this. A well-developed plant should show six or more finely developed fronds arranged cup-fashion round the central stem. The shape of the leaf of the Male Fern is roughly lanceolate, broadest in the middle and tapering at each end. The frond is bi-pinnate, and the pinnæ are long and taper to a fine point. The pinnules are rather blunt, and frequently show serrated edges. The upper portion of the frond is pinnatifid, and in many of the higher pinnæ it is only the pinnules nearest to the rachis that are distinct.

Practically all the fronds are fertile, though the sori occur chiefly on the upper portions of the leaves. The brown patches are to be found arranged in a single line on either side of the central vein of the pinnules. The sorus is circular and is covered with an indusium which is notched or kidney-shaped. In the early days the indusium is of a lead colour, but as the sporangia ripen underneath the brown colouring shows through the thin covering. The foliage of the Male Fern is of a bright green tint, changing to a duller shade as the leaves become older. Not uncommonly the fronds last in good condition through a large part of the winter when the season is mild.

It is now recognized that the Male Fern may be divided into three sub-species. These are called _N. filix-mas_ (_true_), _N. pseudo-mas_, and _N. propinqua_. The differences are not very obvious to the beginner, but it is said that the first named is only partially deciduous—the fronds lying prostrate during the winter. In the case of _N. pseudo-mas_, the fronds are of a leathery nature, and the plant is practically evergreen in sheltered positions. A well-established feature of _N. propinqua_ is that the foliage completely dies away in the autumn.

The Male Fern is abundant in all parts of the United Kingdom where the conditions are in any way suitable. Naturally it is of easy culture in the garden. The new fronds, which are very pretty when they are uncurling, put in an appearance in the month of April.

_Nephrodium Thelypteris._ The specific name of this plant is a compound word derived from the Greek, meaning “ladyfern”; the title probably has reference to the delicate growth of the species. The Fern is also called _Lastrea Thelypteris_. The Marsh Buckler Fern.

This is a very attractive Fern, and perhaps the only British species which frequently grows in water. The Marsh Buckler Fern has a creeping rhizome from which arise the fronds at intervals; these are of two kinds, barren and fertile. The barren fronds sometimes reach the length of four feet, the stipes—which is slender and of a pale green colour—being about equal to the leafy portion. The fertile fronds are usually shorter. In both cases the outline of the fronds is the same, being lanceolate. In each case, too, the pinnæ arranged alternately on either side of the rachis are cut almost to the midrib. In the case of the fertile fronds the pinnæ are perhaps a little more contracted; also the margins are inclined to bend over in such a way as to protect the sori. The clusters of sporangia are almost circular, and these are borne on the margins of the lobes on the underside of the pinnæ. The clusters of the sporangia are covered with small indusia which are slightly notched. The indusia are soon thrown off when the spore cases start to develop.

The Marsh Buckler Fern is not uncommon, and in suitably moist positions is often very abundant. It is, however, said to be rare in Scotland. The species will not flourish in a garden unless something in the way of a bog can be provided. The fronds appear in the spring and are cut down by the first frost.

_Nephrodium oreopteris._ The specific name is connected with the Greek word _oros_, “a mountain.” In some books this fern is also called _N. montana_ and _Lastrea montana_. In certain districts, varieties of the species are common. The Mountain Buckler Fern.

In certain respects this species bears a resemblance to the Male Fern. The fronds spring from a tufted root-stock and their outline is lanceolate; they are from one to four feet in length. The foliage of the Mountain Buckler Fern is of a pale green colour. A distinctive feature is the manner in which the frond of this Fern tapers to a point at both ends; this is even more pronounced at the base than at the apex. In the Male Fern any tapering at the base is of a very slight description. The Mountain Buckler Fern is once pinnate, the pinnæ being continued almost through the entire length of the stalk; this makes the stipes very short. The pinnæ, which are generally placed opposite to one another, are cut very deeply.

The sori are much more abundant on the upper portion of the frond; we shall find them on the back of the leaf along the margins of the lobes. They are covered by a very slight indusium, which soon falls off. In the Mountain Buckler Fern there are to be detected a number of tiny glands on the back of the frond; these are responsible for rather a pleasant odour when the foliage is passed through the hand.

The Mountain Buckler Fern grows on heaths, and it has been found in almost all parts of the United Kingdom. In certain parts of Scotland it is said to clothe the mountain sides with a wonderfully vigorous growth. It is not, however, as its name seems to imply, strictly a mountain species; for it often grows in lowland districts. In cultivation, the species should be given a moist situation. The Mountain Buckler Fern dies down in the winter and the new fronds appear in the spring.

_Nephrodium cristatum._ The specific name of this Fern simply means “crested,” and has reference to the fringed border of the frond. It may be pointed out, however, that there are not a few Ferns on which the name _cristatum_ could with more reason have been bestowed. This species is also called _Lastrea cristatum_. There are a number of forms of this Fern.

This is a very handsome Fern, and it is a pity that it is not more common. The fronds are somewhat oblong in outline and have a very narrow appearance. The root-stock has a creeping habit and sends up tufts of fronds at intervals. These are very erect, and usually measure between one and three feet. The stipes is shorter than the leafy portion, and it bears a few brown scales. The pinnæ are arranged alternately on the rachis and these are not again divided, although they are very deeply cut. The colour of the fronds is of a bright green.

The sori are borne in lines on either side of the mid-vein of the lobe. These are covered at first by an indusium which is notched after the manner of that of the Buckler Ferns.

The Crested Buckler Fern is very rare, though it is found in a few localities—chiefly in the North of England. As a rule it occurs on boggy heaths, and if these conditions can be imitated in the garden, the Fern grows freely. The fronds are soon cut down by the autumn frosts, and the new growth does not appear until May.

_Nephrodium spinulosum._ The specific name means that the plant has little spines. This Fern is associated with other forms, and in some quarters has not been regarded as a definite species at all. Some of the varieties, or, as some authorities say, actually distinct species, with which it is associated have been called _N. dilatatum_ and _N. uliginosa_. It may be mentioned that some botanists consider _N. dilatatum_ to be the most important of the three forms. The chief points about _N. dilatatum_ are the very dark green fronds which are extremely broad at the base; these spring from a massive caudex. The whole plant has a very robust appearance, and it is exceedingly common. Providing the situation is shady this Fern is not particular as to its place of growth. In the same way the preceding species _N. cristatum_ is regarded by some as a doubtful species. On this account the beginner will find _N. spinulosum_ rather difficult to identify, and he must be prepared for departures from the present type which is here described. The Prickly Buckler Fern.

The frond of this species rises from an erect root-stock. The length of the leaves varies from one to three feet, and the stipes is usually about a third of this in measurement. The fronds are triangular in outline, and it is seen that the pinnules nearest to the rachis are considerably larger than the upper ones. This gives a very tapering appearance to the pinnæ. The borders of the pinnules are deeply cut, and the lobes are adorned with tiny points which give a somewhat prickly appearance. The lobes are most prominent on the lowest pinnules, and are also far more pronounced on the lowest pinnæ than they are on the upper divisions of the frond.

The sori are placed on small veins which grow outwards from the midrib of the pinnule. These are covered with kidney-shaped indusia. As has been indicated, the Prickly Buckler Fern varies enormously, both in size and in almost every other particular.

The Prickly Buckler Fern is not uncommon in parts of England, and is to be found in damp woods, especially by the sides of streams. It seems to be less abundant in other parts of the kingdom. It is of easy culture in the garden. The Prickly Buckler Fern retains its fronds through the winter.

_Nephrodium æmulum._ Here the specific name is taken from a Latin word meaning “comparable with”; the reference is to the similarity of the species of _N. spinulosum_. Some botanists have considered that _N. æmulum_ is merely a variety of _N. spinulosum_, though the species seems to be quite distinct. The species is also called _Lastrea æmula_; _L. fœniscii_ and _L. recurva_. The Hay Scented or Triangular Buckler Fern.

A very characteristic feature of this species are the upturned margins of the fronds. This makes the leaf look as if it was curled, and at the same time renders the upper surface of the frond concave. The outline of the fronds is roughly triangular, being widest at the base. The fronds are about one or two feet in length, and the stipes is about equal to the leafy portion. The pinnæ are arranged either in pairs or alternately on either side of the stalk. These are divided into pinnules which, in some cases, towards their bases are again divided. The fronds are of an exceptionally bright green colour, and when bruised give out a pleasant odour not unlike that of new hay. This is due to the secretions of small glands which are to be found on the undersides of the fronds.

The sori on the backs of the fronds are arranged in lines on either side of the mid-veins of the lobes. These are covered with kidney-shaped indusia.

The Hay Scented Buckler Fern cannot be said to be common, although it has a wide distribution and may turn up in unexpected places. It is more abundant in the West of England and in Ireland than elsewhere. It only flourishes in damp places, and this point must be borne in mind when planting it in the garden. The Hay Scented Buckler Fern is an evergreen species.

_Nephrodium rigidum._ The specific name—Latin for “stiff”—is evidently bestowed on the plant on account of its erect habit of growth. The species is also called _Lastrea rigida_. The Rigid Buckler Fern.

This species is quite the rarest of all the Buckler Ferns. The plant has a thickish root-stock from which arise the fronds, usually about a foot in length. The stipes is, as a rule, about half the length of the entire leaf; the bare portion of the stalk is thickly covered with brown scales. The outline of the frond is somewhat variable; on occasion, examples may be found with a lanceolate outline, whilst others may be distinctly triangular in shape. The frond is bi-pinnate, the pinnate being placed rather irregularly on either side of the rachis. The pinnules are blunt and somewhat oblong in shape; they have serrated edges, but do not bear any spines.

The sori are placed on either side of the vein in the middle of the pinnules. These are covered in their early stages with kidney-shaped indusia. Sometimes this frond has a slight fragrance when it is bruised.

The Rigid Buckler Fern is really a mountain species, and generally grows at an elevation of more than a thousand feet above sea-level. It is fairly common in parts of Yorkshire and in some of the north-western counties of England, otherwise it is a real rarity. It is not difficult to grow in the garden, but as it flourishes best in a limestone soil it is a good plan to mix bits of this rock up with the soil which is used. The new fronds appear in May and die down during the winter.

_Polystichum (Aspidium) lonchitis._ Here the generic name is based on two Greek words, _polys_, “many,” _stichos_, “order”; the specific name is also derived from another Greek word—_lonche_, “a spear,” this referring to the narrow spear-like appearance of the fronds. The Holly Fern.

This species, on account of its regular habit of growth and generally stiff appearance, is an easy one to identify. The fronds arise from a tufted root-stock, and in average specimens would be about nine inches in length. This might be greater or less, according to the conditions under which the particular plant was living. The shape of the fronds is narrowly lanceolate, and there is a very short stipes which is thickly covered with scales. The leaves of the Holly Fern are once pinnate, the pinnæ being ovate and having a curious ear-shaped enlargement at their bases on the upward side. The edges of the pinnæ are adorned with a number of sharp teeth, and this gives a singular spiny appearance to the whole plant. On this account the Fern has probably received its popular name of Holly Fern. The colour of the foliage is of a very pretty bright green tint.

The Holly Fern, as indeed are all the species of _Polystichum_, is very distinct from a _Nephrodium_ in the matter of its indusium. This is quite circular, and has no notch; moreover, it is attached to the pinnules by a short stalk in the centre. Thus it is proper to describe the shape of the indusium as peltate. The sori are chiefly confined to the upper portion of the back of the frond, and are situated on either side of the midrib of the pinnæ. After the falling away of the indusia the sori tend to spread, so that they may finally cover almost the whole of the back of the fertile pinnæ.

The Holly Fern is essentially a plant of the mountains, and it is often found growing in the most exposed situations. It is not common in England, though it has been found in a few localities in the north. The species has a much wider distribution in Scotland. The Holly Fern is evergreen in habit, and its stiff fronds seem to be able to withstand the severest frost. The plant is rather a difficult one to grow, though if it can be given a rock crevice it will sometimes settle down happily in the garden. The foliage of the Holly Fern lasts through the year.

_Polystichum (Aspidium) aculeatum._ In this case the specific name is a Latin term simply meaning “provided with prickles”—an allusion to the fact that the fronds are adorned with spines. The Hard Prickly Shield Fern.

This species is very distinct in its general appearance from the Holly Fern, though it can at once be seen to be a Shield Fern by the unnotched indusia which cover the sori. The fronds may be as much as two feet in height, or even a little more, and these rise from a tufted root-stock. As a rule the stipes is very much shorter than the leafy portion, and both it and the rachis are thickly covered with scales. The outline of the frond is lanceolate, and the colour of the foliage is dark green. A pretty glossy effect is noticeable on the upper surface. The frond of the Hard Prickly Shield Fern is twice divided, and the pinnæ are arranged alternately on either side of the rachis. A distinctive point about this species is that the upper pinnules at the base of each pinna is larger in all ways than the other pinnules. The pinnules are provided with sharp teeth, and it should be noted that they have nothing very decided in the way of stalks. Actually they are what botanists call decurrent—that is, tending to run together at the base. In some varieties of this species the tendency is more marked than in others.

The sori are placed on either side of the mid-veins of the pinnules, and these are usually confined to about half the upper portion of the back of the frond.

The Hard Prickly Shield Fern is very widely distributed in England, and it is to be looked for in shady woods. It is an exceedingly easy plant to grow, and thrives even in town gardens. The plant is evergreen in habit.

_Polystichum (Aspidium) angulare._ It is not regarded by some botanists as an established species, but is thought to be a variety of _A. aculeatum_. However, there are certain differences which appear to be specific. The Soft Prickly Shield Fern.

As in the Hard Prickly Shield Fern, we find a tufted root-stock from which grow lanceolate fronds. We notice the same short stipes and the narrow pinnæ on the leafy portion tapering to a point. In this species it is said that the pinnules at the base are more nearly equal in size than is the case with _A. aculeatum_. The pinnules are also more definitely stalked in the former than in the latter. In the case of the Soft Prickly Shield Fern, it is noticeable that all parts of the stalk of the frond—both stipes and rachis, and even the rachides—are covered with brown scales. It is said, too, that the droop of the fronds is more pronounced in the Soft Prickly Shield Fern than in the Hard Prickly Shield Fern.

The arrangement of the sori is similar in both species.

The Soft Prickly Shield Fern has been found widely distributed in England and Ireland, though it is not so common in other parts of the United Kingdom. It is easily cultivated, and is evergreen in habit.

_Woodsia hyperborea._ The generic name of this species commemorates the botanist, Mr. Joseph Woods; the specific name is taken from two Greek words—_hyper_, “beyond,” and _Boreas_, “the north wind,” without doubt a reference to the fact that the species extends to the Arctic regions. The plant is also called _Woodsia alpina_. The Alpine Woodsia.

This is a very pretty little Fern. The tiny fronds, which are not more than two or three inches in length, spring from a tufted root-stock. The stipes is rather short and bears a few brown scales. The outline of the frond is oblong, and the leaf tapers slightly towards the base as well as at the apex. The fronds are once pinnate, and the pinnæ, which are lobed, are arranged in rather an irregular fashion on either side of the leaf-stalk. A curious feature of the Alpine Woodsia is that the fronds are jointed just above their connexion with the root-stock. When the leaves die the stalks break away at this point and leave the bases behind.

When the back of the frond is examined it is evident that we have here a very distinctive feature. The patches of spore cases are covered with a very thin indusium, and as time goes on this splits into divisions which resemble a number of hairs. The fronds are of rather a stout texture for so small a Fern, and in all parts show an inclination to be hairy.

The Alpine Woodsia is a very rare Fern, and there are only a few recorded localities of it in England and Wales. It makes its home on moist rocks on the slopes of high mountains. This little Fern is fairly easily cultivated. The fronds disappear in the winter.

_Woodsia ilvensis._ The specific name refers to the island of Elba (Ilva), where this plant was first of all discovered. In some quarters this plant is held to be merely a variety of _W. hyperborea_. The Oblong Woodsia.

The fronds of this Fern rise from a tufted root-stock. The stipes is short, but the frond as a whole is larger than that of the Alpine Woodsia, and may be as much as six inches in length. The outline of the fronds is oblong, tapering towards the base and at the apex. Over the whole frond, both on the upper and the lower side, is a covering of fine hairs. Usually the hairiness of the Oblong Woodsia is very pronounced. The covering is so thick on the underside that it is rather difficult to discover the sori. These have the same curious divided indusia to be observed in the Alpine Woodsia.

The Oblong Woodsia is a very rare Fern, only to be found in mountainous districts. It has been reported from a few localities in England and also occurs in Scotland, usually in almost inaccessible places. The fronds die down in the winter and break away from the stem just at the crown of the root-stock.

_Cystopteris fragilis._ The generic name of this Fern is formed of the two Greek words _kystos_, “a bladder,” and _pteris_, “a fern.” The specific name is, of course, a Latin word which means “easily broken.” The Brittle Bladder Fern.

This is one of the most beautiful of all our native Ferns. From a tufted root-stock which is clad with pale brown scales the fronds arise; these are about six or eight inches in length and are lanceolate in outline. This Fern has a habit of spreading in such a way, that each plant may have several of the tufted crowns from each of which arise a cluster of fronds. These are sometimes once, and on other occasions, twice pinnate. The pinnæ are about an inch in length, and where there are pinnules these are toothed.

We shall find the sori on veins which run from the mid-vein of the pinnules. The spore patches are rounded and are covered with a curious indusium, with an inflated appearance towards the centre. It is from the resemblance of this indusium to a bladder that the plant has received its popular name. With the disappearance of the indusia the sori tend to spread over the whole surface of the back of the frond. The general appearance of the Brittle Bladder Fern is of a delicate nature and it has a very distinctive appearance.

Properly speaking, the Brittle Bladder Fern is a mountain species, though it sometimes occurs on old walls or in rocky clefts which are not very elevated. The species is widely distributed in all parts of Great Britain, though in frequented districts it is soon exterminated. The Brittle Bladder Fern does not seem to grow very well in the open rockery, though it is fairly easy to cultivate in pots. The fronds die down at the approach of winter. There are a certain number of varieties.

_Cystopteris montana._ Here the specific name is formed from the Latin word _mons_, “a mountain.” The Mountain Bladder Fern.

This is the only other recognized species of Bladder Fern to be found in the United Kingdom. The species has a slender creeping underground stem from which arise the delicate fronds. These are usually about four to eight inches in length, and the stipes is considerably longer than the leafy portion. The design of the frond is rather like that of the three-branched Polypody, this being due to the fact that the lowest pair of pinnæ is much larger than any of the others.

The general outline of the fronds is wedge-shaped, and these are very finely divided. Indeed in a well-developed leaf the fronds may be three or even four times pinnate. The pinnules themselves are also deeply cut. It will be noticed that the lower portion of the frond is always more freely divided than the upper part; a common characteristic in Ferns.

The sori are very freely scattered on the lobes or pinnules at the back of the frond, and these are covered with the curious hooded indusia which were noticed in the last species.

The Mountain Bladder Fern is perhaps the rarest of all our native species. It is at home in mountainous districts, and seems only to have been noticed in a few localities in Wales and Scotland. Probably it would be seen more often were it not that it grows in positions which are not of easy access. It should be given the same treatment in the garden as that recommended for the Brittle Bladder Fern. The fronds disappear in the winter.

In some books a species is given, known as _Cystopteris alpina_ or _regia_. The plant nearly resembles _Cystopteris fragilis_, although it is somewhat smaller. This is a very doubtful native, as it seems only to have been recorded in one or two localities where it may have been naturalized.