product of the normal or sexual mode of propagation in the group,
but owes its origin to a peculiar type of budding or non-sexual
reproduction, in which, as temporary resting or protecting structures,
the vesicular bodies may have had a share.
As respects the mode of life of the Graptolites there can be little doubt that the Dendroidea were, with some exceptions, sessile or benthonic animals, their polyparies, like those of the recent Calyptoblastea, growing upwards, their bases remaining attached to the sea floor or to foreign bodies, usually fixed. The Graptoloidea have also been regarded by some as benthonic organisms. A more prevalent view, however, is that the majority were pseudo-planktonic or drifting colonies, hanging from the underside of floating seaweeds; their polyparies being each suspended by the nema in the earliest stages of growth, and, in later stages, some by the nemacaulus, while others became adherent above by means of a central disk or by parts of their dorsal walls. Some of these ancient seaweeds may have remained permanently rooted in the littoral regions, while others may have become broken off and drifted, like the recent Sargassum, at the mercy of the winds and currents, carrying the attached Graptolites into all latitudes. The more complex umbrella-shaped colonies of colonies (synrhabdosomes) described as provided with a common swimming bladder (pneumatophore?) may have attained a holo-planktonic or free-swimming mode of existence.
The range of the Graptolites in time extends from the Cambrian to the Carboniferous. The Dendroidea alone, however, have this extended range, the Graptoloidea becoming extinct at the close of Silurian time. Both groups make their first appearance together near the end of the Cambrian; but while in the succeeding Ordovician and Silurian the Dendroidea are comparatively rare, the Graptoloidea become the most characteristic and, locally, the most abundant fossils of these systems.
The species of the Graptoloidea have individually a remarkably short range in geological time; but the geographical distribution of the group as a whole, and that of many of its species, is almost world-wide. This combination of circumstances has given the Graptoloidea a paramount stratigraphical importance as palaeontological indices of the detailed sequence and correlation of the Lower Palaeozoic rocks in general. Many Graptolite zones, showing a constant uniformity of succession, paralleled in this respect only by the longer known Ammonite zones of the Jurassic, have been distinguished in Britain and northern Europe, each marked by a characteristic species. Many British species and associations of genera and species, occurring on corresponding horizons to those on which they are found in Britain, have been met with in the graptolite-bearing Lower Palaeozoic formations of other parts of Europe, in America, Australia, New Zealand and elsewhere.
Bibliography.—Linnaeus, Systema naturae (12th ed. 1768); Hall, Graptolites of the Quebec Group (1865); Barrande, Graptolites de Bohème (1850); Carruthers, Revision of the British Graptolites (1868); H. A. Nicholson, Monograph of British Graptolites, pt. 1 (1872); id. and J. E. Marr, Phylogeny of the Graptolites (1895); Hopkinson, On British Graptolites (1869); Allman, Monograph of Gymnoblastic Hydroids (1872); Lapworth, An Improved Classification of the Rhabdophora (1873); The Geological Distribution of the Rhabdophora (1879, 1880); Walther, Lebensweise fossiler Meerestiere (1897); Tullberg, Skånes Graptoliter (1882, 1883); Törnquist, Graptolites Scanian Rastrites Beds (1899); Wiman, Die Graptolithen (1895); Holm, Gotlands Graptoliter (1890); Perner, Graptolites de Bohème (1894–1899); R. Ruedemann, Development and Mode of Growth of Diplograptus (1895–1896); Graptolites of New York, vol. i. (1904), vol. ii. (1908); Frech, Lethaea palaeozoica, Graptolithiden (1897); Elles and Wood, Monograph of British Graptolites (1901–1909). (C. L.*)
GRASLITZ (Czech, Kraslice), a town of Bohemia, on the Zwodau, 145 m. N.W. of Prague by rail. Pop. (1900) 11,803,
exclusively German. Graslitz is one of the most important
industrial towns of Bohemia, its specialities being the manufacture
of musical instruments, carried on both as a factory and
a domestic industry, and lace-making. Next in importance are
cotton-spinning and weaving, machine embroidery, brewing,
and the mother-of-pearl industry.
GRASMERE, a village and lake of Westmorland, in the heart
of the English Lake District. The village (pop. of urban district
in 1901, 781) lies near the head of the lake, on the small river
Rothay and the Keswick-Ambleside road, 1212 m. from Keswick
and 4 from Ambleside. The scenery is very beautiful; the valley
about the lakes of Grasmere and Rydal Water is in great part
wooded, while on its eastern flank there rises boldly the range
of hills which includes Rydal Fell, Fairfield and Seat Sandal,
and, farther north, Helvellyn. On the west side are Loughrigg
Fell and Silver How. The village has become a favourite centre
for tourists, but preserves its picturesque and sequestered
appearance. In a house still standing William Wordsworth
lived from 1799 to 1808, and it was subsequently occupied by
Thomas de Quincey and by Hartley Coleridge. Wordsworth’s
tomb, and also that of Coleridge, are in the churchyard of the
ancient church of St Oswald, which contains a memorial to
Wordsworth with an inscription by John Keble. A festival
called the Rushbearing takes place on the Saturday within the
octave of St Oswald’s day (August 5th), when a holiday is
observed and the church decorated with rushes, heather and
flowers. The festival is of early origin, and has been derived by
some from the Roman Floralia, but appears also to have been
made the occasion for carpeting the floors of churches, unpaved
in early times, with rushes. Moreover, in a procession which
forms part of the festivities at Grasmere, certain Biblical stories
are symbolized, and in this a connexion with the ancient miracle
plays may be found (see H. D. Rawnsley, A Rambler’s Note-Book at the English Lakes,
Glasgow, 1902). Grasmere is also noted for
an athletic meeting in August.
The lake of Grasmere is just under 1 m. in length, and has an extreme breadth of 766 yds. A ridge divides the basin from north to south, and rises so high as to form an island about the middle. The greatest depth of the lake (75 ft.) lies to the east of this ridge.
GRASS AND GRASSLAND, in agriculture. The natural
vegetable covering of the soil in most countries is “grass”
(for derivation see Grasses) of various kinds. Even where
dense forest or other growth exists, if a little daylight penetrates
to the ground grass of some sort or another will grow. On
ordinary farms, or wherever farming of any kind is carried out,
the proportion of the land not actually cultivated will either
be in grass or will revert naturally to grass in time if left alone,
after having been cultivated.
Pasture land has always been an important part of the farm, but since the “era of cheap corn” set in its importance has been increased, and much more attention has been given to the study of the different species of grass, their characteristics, the improvement of a pasture generally, and the “laying down” of arable land into grass where tillage farming has not paid. Most farmers desire a proportion of grass-land on their farms—from a third to a half of the area—and even on wholly arable farms there are usually certain courses in the rotation of crops devoted to grass (or clover). Thus the Norfolk 4-course rotation is corn, roots, corn, clover; the Berwick 5-course is corn, roots, corn, grass, grass; the Ulster 8-course, corn, flax, roots, corn, flax, grass, grass, grass; and so on, to the point where the grass remains down for 5 years, or is left indefinitely.
Permanent grass may be grazed by live-stock and classed as pasture pure and simple, or it may be cut for hay. In the latter case it is usually classed as “meadow” land, and often forms an alluvial tract alongside a stream, but as grass is often grazed and hayed in alternate years, the distinction is not a hard and fast one.
There are two classes of pasturage, temporary and permanent. The latter again consists of two kinds, the permanent grass natural to land that has never been cultivated, and the pasture that has been laid down artificially on land previously arable and allowed to remain and improve itself in the course of time. The existence of ridge and furrow on many old pastures in Great Britain shows that they were cultivated at one time, though perhaps more than a century ago. Often a newly laid down pasture will decline markedly in thickness and quality about the fifth and sixth year, and then begin to thicken and improve year by year afterwards. This is usually attributed
