To this attitude he offered uncompromising opposition, and by the synthetical production of numerous hydrocarbons, natural fats, sugars and other bodies he proved that organic compounds can be formed by ordinary methods of chemical manipulation and obey the same laws as inorganic substances, thus exhibiting the "creative character in virtue of which chemistry actually realizes the abstract conceptions of its theories and classifications - a prerogative so far possessed neither by the natural nor by the historical sciences."
The French census uses the commune as the basis of its returns, and employs the following classifications in respect to communal population: (I) Total communal population.
At present, therefore, classifications of the Hydromedusae have a more or less tentative character, and are liable to revision with increased knowledge of the life-histories of these organisms. Many groups bear at present two names, the one representing the group as defined by polyp-characters, the other as defined by medusa-characters.
Delage and Herouard (Hydrozoa ) were the first to make an heroic attempt to unite the two classifications into one, to which Hickson (Hydrozoa ) has made some additions and slight modifications.
52), referable to the family Clavidae; a fact sufficient to Indi a cate the tentative character of even the most modern classifications of this order.
One of the best known classifications on these lines is that by Warming.1 Warming recognized and defined four ecological classes as follows: Hydrophytes.These live in a watery or wet substratum, with at least 80% of water.
Existing classifications, however, do not take account of any difference in kind between mountain and hills, although it is common in the German language to speak of Hiigelland, Mittelgebirge and Hochgebirge with a definite significance.
Fossil Birds Much had naturally been expected from the study of fossil birds, but, so far as the making of classifications is concerned, they have proved rather a source of perplexities.
So long as the characters of new fossils are only of specific and generic value, it is mostly possible to assign the birds to their proper place, but when these characters indicate new families or orders, for instance Hesperornithes, Ichthyornithes, Palaelodi, their owners are put outside the more tersely constructed classifications applicable to modern birds.
Our artificially-established classifications collapse whilst we gain further insight into the mutual affinities of the existing groups.
In recent years classifications in part agreeing with the older schemes but largely original, in accord with researches on the comparative anatomy of the insects, have been put forward.
But none of these classifications of expense reaches the root of the matter.
The two authors were in constant communication, and the classifications they adopted had much in common.
The offendicula have sometimes been looked upon as an anticipation of Francis Bacon's Idola, but the two classifications have little in common.
Sharpe (1891), whilst in most of the other numerous classifications the Ratitae (vicariously named Struthiones, Cursores, Brevipennes, Proceres) were treated as of much lower rank.
A further differentiation of the provinces of chemistry and physics is shown by the classifications of matter.
Such classifications have been at- Classif1- tempted by A.
Thus not only did Darwin's theory give a new basis to the study of organic 'structure, but, whilst rendering the general theory of organic evolution equally acceptable and Effects of necessary, it explained the existence of low and simple forms of life as survivals of the earliest ancestry of theory more highly complex forms, and revealed the classifications of the systematist as unconscious attempts to construct the genealogical tree or pedigree of plants and animals.
The last of these was that of Louis Agassiz (1807-1873), who, whilst surveying all previous classifications, propounded a scheme of his own (Essay on Classification, 1859), in which, as well as in the criticisms he applies to other systems, the leading notion is that sub-kingdoms, classes, orders and families have a real existence, and that it is possible to ascertain and distinguish characters which are of class value, others which are cnly of ordinal value, and so on; so that the classes of one sub-kingdom should on paper, and in nature actually do, correspond in relative value to those of another sub-kingdom, and the orders of any one class similarly should be so taken as to be of equal value with those of another class, and have been actually so created.
Thus it came about not only that classifications of disease based on superficial likeness - such as jaundice, dropsy, inflammation - were broken up, and their parts redistributed, but also that even more set diseases began to lose their settlements, and were recognized as terms of series, as transitory or culminating phases of perturbations which might be traced to their origins, and in their earlier stages perhaps withstood.
For general classifications see F.
Both classifications are of universals, concepts or general terms, proper names of course being excluded.
The Nuovo Prospetto delle scienze economiche (1815-1817), although long to excess, and overburdened with classifications and tables, contains much valuable material.
Placed by most systematists in the family Scolopacidae, the birds commonly called Sandpipers seem to form three sections, which have been often regarded as Subfamilies - Totaninae, Tringinae and Phalaropodinae, the last indeed in some classifications taking the higher rank of a Family - Phalaropodidae.
Restrictions upon the taxing power, and unwise classifications of property for taxation purposes, embodied without good understanding in state constitutions, have been a primary obstacle to the development of sound systems of taxation in the several states.
We are familiar enough in the West with similar classifications, summed up in such expressions as the Seven Deadly Sins, the Ten Commandments, the Thirty-nine Articles, the Four Cardinal Virtues, the Seven Sacraments and a host of others.
Other classifications which are extensively used are those respectively of K.
In most of the older classifications great importance was attached to these physiological characters, and a number of genera were established which, owing to the numerous annectent forms which have since been discovered, must be abandoned.
There was also sufficient comprehension of the differences between the main classes of Echinoderms - the sea-urchins or Echinoidea, the starfish or Asteroidea, the brittle-stars and their allies known as Ophiuroidea, the worm-like Holothurians, the feather-stars and sea-lilies called Crinoidea, with their extinct relatives the sac-like Cystidea, the bud-formed Blastoidea, and the flattened Edrioasteroideawhile within the larger of these classes, such as Echinoidea and Crinoidea, fair working classifications had been established.
The morphologist may propose classifications, and the embryologist may erect genealogical trees, but all schemes which do not agree with the direct evidence of fossils must be abandoned; and it is this evidence, above all, that gained enormously in volume and in value during the last quarter of the 19th century.
This class shows much greater diversity of organization than any other, and the classifications proposed by recent writers, such as E.
Other general classifications of taxes have also been attempted, as, for instance, taxes upon real property, and taxes upon personal property, and so on.
Such classifications are, however, uninstructive, and it has been found practically necessary in financial writing to take the principal taxes by name, or by such a general grouping as that of import or stamp duties, and then describe their nature, characteristics and incidence.
(For particulars of Quetelet's method, see his Physique sociale (1869), and Anthropometrie (1871).) Classifications of man have been numerous, and though, regarded as systems, most of them are unsatisfactory, yet they have been of great value in systematizing knowledge, and are all more or less based on indisputable distinctions.
The principal attempts at morphological classifications recently brought forward are those of de Toni and Trevisan (1889), Fischer (1897) and Migula (1897).