Lives of Eminent Zoologists, from Aristotle to Linnaeus Part 18

The above cla.s.ses contain all the plants that are _Phoenogamous_, or have distinctly perceptible organs of reproduction; the next and last cla.s.s is composed of the _cryptogamous_, or those of which the flowers either do not exist, or have not been demonstrated.

XXIV. CRYPTOGAMIA: Ferns, mosses, lichens, sea-weeds, mushrooms, &c.

The orders or subdivisions of the cla.s.ses are founded on the number of the pistils in the first thirteen. Thus, in any of these cla.s.ses, the first order is _Monogynia_, or one pistil; the second _Digynia_, two pistils, &c. But in the fourteenth cla.s.s, Didynamia, there are only two orders, _Gymnospermia_ and _Angiospermia_, the former having four naked seeds, the latter having the seeds enclosed in a seed-vessel. In the fifteenth cla.s.s, Tetradynamia, there are also two orders, _Siliculosa_, in which the pod is short, and _Siliquosa_, in which it is long. The orders of Monadelphia, Diadelphia, and Polyadelphia, are formed from the number of the stamina, and bear the names of _Hexandria_ when there are six, _Decandria_ when there are ten, &c. The orders of the nineteenth cla.s.s, Syngenesia, are six. In the first, _Polygamia aequalis_, all the flowers (or _florets_, as they are here called on account of their small size, and because they are viewed as components of a compound flower) have stamens and pistils, and are equally fertile; in the second, _Polygamia superflua_, the flowers of the centre have stamens and pistils, those of the circ.u.mference pistils only, but both kinds produce seeds; in the third, _Polygamia frustranea_, the flowers of the centre have stamens and a pistil, and are fertile, those of the circ.u.mference neutral, or furnished with a pistil, but steril; in the fourth, _Polygamia necessaria_, the flowers of the centre have stamens and a pistil, but are steril, in consequence of an imperfection in the stigma, those of the circ.u.mference have a pistil, and are fertile; in the fifth, _Polygamia segregata_, all the flowers are perfect, but each has a small calyx, and the whole are contained within a common involucre; and in the last order, _Monogamia_, the flowers are separated from each other. In Gynandria, the orders are determined by the number of the stamens. In Monoecia and Dioecia, the characters distinctive of the cla.s.ses are employed for the orders. Polygamia has three orders, _Monoecia_, _Dioecia_, _Trioecia_; and the last cla.s.s, Cryptogamia, is divided into four orders, consisting of the _Filices_ or _Ferns_, the _Musci_ or Mosses, the _Algae_, and the _Fungi_.

The genera are established upon characters derived from all the parts of fructification compared together, according to their number, figure, proportion, and situation; but as this volume was intended to contain all the plants known to the author, the _natural_ characters thus formed could not be employed on account of their length, and he has used the _essential_ character, which is shorter, and consists of those marks that serve to distinguish the genera from each other in the natural orders; while at the head of each cla.s.s, the genera are synoptically disposed, being defined by their _fact.i.tious_ characters, or those by which one is distinguished from another in the artificial order only.

The remarks which we have already made respecting the generic and specific names, apply equally to this department. These last, in the systems of former botanists, were lengthened descriptions, taken from various circ.u.mstances, and seldom in any degree distinctive; but Linnaeus reduced them to twelve words at most, and derived them from some remarkable difference in the leaves, roots, stems, or other unvarying properties. These short phrases he continued to call the specific name, but they are now properly considered as the specific character; while he invented what he called the _trivial_ name, consisting of a single word added to the generic, and which we now use as the specific. The number of species mentioned in the Systema Naturae amounts to upwards of 7800.

We come now to the third and last volume, containing his arrangement of the objects forming the mineral kingdom. This department has received less elucidation from him than the others. In 1736, he first digested a mineralogical system, in which he attempted to found the genera on definite characters; but he seems to have lost sight of the subject until obliged to attend to it when editing the twelfth edition of his work. There he prefixes to his arrangement a brief account of his theory on the origin of fossil bodies in general, and of their several combinations. His views, however, are extremely fanciful, and cannot be said to have produced any beneficial effect on the study of this science. As they have long ago pa.s.sed into oblivion, it may afford amus.e.m.e.nt, if not instruction, to present an outline of them.

The earth originated from water, agreeably to the testimony of Moses, Thales, and Seneca! The sea becoming pregnant gradually produced the dry land, from which the dew rose by evaporation, was elevated into clouds, and again descended in showers. No certain indications of a universal deluge have yet been found, but we every where perceive that land has been formed from the sea.

The water of the ocean, being impregnated by the air, produces a twin birth; the _saline_ principle, which is masculine, soluble, acrid, transparent, and crystalline; the _earthy_, which is feminine, fixed, viscid, opaque, and attractive. It also nourishes the animal and the vegetable beings, which in course of time are reduced to earth.

The _salts_, which are sapid, polyhedral, transparent, multiplicative, soluble into infinitely minute particles, although always retaining the same form, and again becoming concrete so as to form larger particles of the same figure, generate various minerals by crystallizing.

_Nitrum_, which is aerial, by covering over increases _sand_.

_Muria_, which is marine, by corroding attracts _clay_.

_Natrum_, which is of animal origin, by deliquescing coagulates _lime_.

_Alumen_, which is of vegetable origin, by ramifying produces _earthy soil_.

These are the _Fathers_ of minerals.

The _Earths_, which are powdery, drying, soluble, fixed, primitive, are generated or reproduced by crystallizing, precipitating, fermenting, or putrefying. From them, by crystallization or attraction, minerals are reformed, and these again are resolved into earths and regenerated.

_Clay_ is the precipitation of the viscid water of the sea; and is opaque, plastic, friable, capable of hardening, and fireless.

_Sand_ is the crystallization of turbid rain-water; and is transparent, juiceless, giving sparks, durable, and capable of being vitrified.

_Mould_ is the decomposition of fermenting vegetables; and is black, bibulous, powdery, and combustible.

_Lime_ is the decomposition of putrescent animal substances; and is whitish, absorbent, mealy, penetrable, and effervescent.

Clay, the earth of sea-water, is hardened into _talc_, when redissolved is regenerated in the form of _asbestus_, and when more intimately dissolved resumes the form of _mica_. Sand, the earth of rain-water, when thrown on the land and dried, forms _drift-sand_, which finally becomes _gravel_. Both substances, when under ground, are converted into _sandstone_, and when mixed with other matters form _pebbles_, which grow into _stones_. When redissolved and crystallized, it produces _quartz_. _Mould_, the earth of vegetables, is hardened into fissile slate, which being impregnated with bitumen becomes _coal_. It is dissolved into _ochre_, and regenerated into _tophus_. Lime, the wife of natron, produces _marble_, dissolved and saturated with acid is crystallized into _gypsum_. Both are decomposed by the elements into _chalk_, which, acted upon by rain-water, becomes _flint_; and when dissolved, is crystallized into _spar_ (or _calcedony_).

Such are the _Mothers_ of minerals.

It is unnecessary to follow our author, while he states the principles of his s.e.xual system of minerals, through the forms and modifications of crystals, metals, rocks, and petrifactions. His scheme of geology may be described as follows:--The strata of the earth are generally parallel to each other, although not always so, nor always of marine origin. The lowest is of sandstone (_cos_), the second of slate, the third of marble filled with marine petrifactions, the fourth of slate, the uppermost of the saxose kind, which includes granite, porphyry, trap, conglomerate, and puddingstone. It is obvious that the ocean has produced the land. It is rendered turbid by nitrous showers, precipitates, and is crystallized into sand, which covers the bottom of the sea. The surface of it is here and there covered over to a great extent with floating fuci, the mould derived from which gradually descends, while the lighter particles help to form a floating meadow. Marine vermes, the mollusca, testacea, lithophytes, and zoophytes, together with fishes and sea-birds, feed beneath this floating meadow. An argillaceous sediment falls down in the quiet water, and this, together with the calcareous sh.e.l.ls of the marine vermes, gradually forms a heap, which rises to the surface, while the pressure agitating the water drives out the marine animals. On the rock thus formed, the sea casts up great quant.i.ties of fuci, which are converted into mould, until at length the sandy earth rises above the surface, dries, is driven about, and concresces into gravel and sandstone. In the course of ages, the sand is hardened into sandstone, the mould into bituminous shale and coal, the clay into marble, other layers of mould into other beds of shale or slate, and other ma.s.ses of sand into gravel and conglomerate. This again is converted into pebbles, these into stones, the stones into rocks. At length, the water subsiding, the ma.s.s becomes a mountain. Had Linnaeus been as unfortunate in his other theories as in this, his name would have been long ago forgotten.

However fanciful his theoretical views may be, his cla.s.sification is not unworthy of praise, and his specific definitions are generally intelligible to a modern mineralogist; but this is nearly all, however, that can be said in their favour. He divides the mineral kingdom into three cla.s.ses, under the names of _Petrae_, _Minerae_, and _Fossilia_.

These are again subdivided into several orders, and the number of genera amounts to fifty-four.

Cla.s.s I. PETRae or STONES, or, as modern geologists would say, ROCKS.

Steril stones, originating from an earthy principle by cohesion; simple, as being dest.i.tute of salt, sulphur, or mercury; fixed, as not being intimately soluble; similar, as consisting of particles united at random.

Order I. HUMOSae. Deposited from vegetable earth, combustible and burning to cinders, their powder harsh and light; as roofing-slate.

Order II. CALCARIae. Originating from animal earth; penetrable by fire, and becoming more porous, their powder mealy; and when burnt, they fall into a fine powder; as limestone, marble, gypsum.

Order III. ARGILLACEae. Originating from the viscid sediment of the sea, becoming harder and stiffer in the fire, their powder unctuous before exposure to fire; as serpentine, asbestus, mica.

Order IV. ARENATae. Originating from precipitation caused by rain-water, when struck with steel emitting sparks, very hard, their powder rough and angular like bits of gla.s.s; as quartz, jasper, flint.

Order V. AGGREGATae. Originating from a mixture of the foregoing, and therefore partic.i.p.ating their const.i.tuent particles; their powder differing accordingly; as granite, puddingstone.

Cla.s.s II. MINERae, MINERALS.

Fertile stones, originating from a saline principle by crystallization; compound, as produced from a stony substance (of the preceding cla.s.s), impregnated by salt, sulphur, or mercury, intimately soluble in an appropriate menstruum, and crystalline.

Order I. SALIA, _Salts_. To be distinguished by the taste, soluble in water; as rock-salt, alum, borax.

Order II. SULPHURA, _Sulphureous Minerals_. Distinguishable by smell, emitting an odour and flaming under the action of fire, soluble in oil; as amber, naphtha, pyrites.

Order III. METALLA, _Metallic Minerals_. Distinguishable by good eyes! very heavy, fusible, soluble in appropriate acid menstrua; as molybdaena, lead, gold, and copper.

Cla.s.s III. FOSSILIA, FOSSILS.

Ambiguous stones, originating from modifications of the substances included in the preceding cla.s.ses.

Order I. PETRIFICATA, _Petrifactions_. Impressed with the form of some natural object, as,--

_Zoolithus_, the petrifaction of an animal of the cla.s.s Mammalia.

_Ornitholithus_, a petrified bird.

_Amphibiolithus_, a petrified frog, snake, &c.

_Ichthyolithus_, a petrified fish.

_Entomolithus_, a petrified insect or crab.

_Helmintholithus_, of the cla.s.s vermes, including sh.e.l.ls.

_Phytolithus_, vegetable petrifactions.

_Graptolithus_, resembling figures produced by painting; as florentine and landscape marble.

Order II. CONCRETA, coagulated from particles agglutinated at random; as urinary and salivary calculi; tartar of wine; pumice, formed by fire; stalact.i.te, formed by air; tophus, produced under water, as oolite.

Order III. TERRae, _Earths_. Pulverized, their particles loose; as ochre, sand, clay, and chalk.

The first edition of the Systema Naturae, which consisted of fourteen folio pages, was, as has been already related, printed at Leyden in 1735. That which the author reckoned the twelfth, but which was in reality the fifteenth, is the one that ought to be referred to by naturalists, it being the last that was published under his own care and inspection. It appeared at Stockholm in 1766.

An edition, greatly enlarged, was published at Leipsic by Gmelin in 1788, and contains numerous species not included in any of the preceding. "No nation," says Dr Stoever, "can produce so complete a repertory of natural history as the above. With infinite labour, exertion, and judgment, all the recent discoveries and observations in all the branches of natural science have been united in it." It is, however, as every one who has had occasion to consult it must be aware, a most injudicious compilation, in which a single species is often described under two, three, or even four different names, and in which no improvement corresponding to the advanced state of the science was made in the grouping of the species or genera.