Sorter

“ Weir-Mitchell treatment in hysterical joint affections, 538
Wens, 389
Wet-cupping, 42
White swelling of joints, 515, 518
Whitlow, 55
gangrene from, 99
at nail fold, 56
purulent blister, 55
subcutaneous, 56
subperiosteal, 58
of tendon sheaths, 57
thecal, 57
Whitlow, of toes, 55
varieties of, 55
Winged scapula, 363
Wool-sorter's disease, 121
Wounds, 220. ”

“ Areas of Distribution.—Every species of animal has a certain area of distribution to which, as a rule, it is permanently confined, although, no doubt, the limits of its range fluctuate somewhat from year to year, and in some exceptional cases may be considerably altered in a few years or centuries. Each species is moreover usually limited to one continuous area, over the whole of which it is more or less frequently to be met with, but there are many apparent and some real exceptions to this rule. ”

“ For the purposes of the study of geographical distribution therefore, we must, except in special cases, consider the true range of a species to comprise all the area which it occupies regularly for any part of the year, while all those districts which it only visits at more or less distant intervals, apparently driven by storms or by hunger, and where it never regularly or permanently settles, should not be included as forming part of its area of distribution. ”

“ If it be supposed that when magnified, each of these dots resolves itself into a cluster of clusters, representing genera and species, an approximate idea will be formed of the relations among the successively-subordinate groups constituting the animal kingdom. Besides the subordination of groups and their general distribution, some other facts are indicated. By the distances of the great divisions from the general centre, are rudely symbolized their respective degrees of divergence from the form of simple, undifferentiated organic matter; which we may regard as their common source. ”

“ As we pointed out in our discussion of these phenomena, the peculiar distribution of factors in these cases must be taken to mean that the planes of division at some critical stage in the segregation are determined with reference to the parental groups of factors, or in other words, that the whole system has a polarity, and that the distribution of factors with reference to this polarity differs according to the grouping of factors in the gametes which united in fertilization to produce the plant. ”

“ If, therefore, we were to divide the population of any species into three groups of equal extent, with regard to any particular character—as length of wing, or of toes, or thickness or curvature of bill, or strength of markings—we should have one group in which the mean or average character prevailed with little variation, one in which the character was greatly, and one in which it was little, developed. ”

“ In cities house refuse should be collected every day, and the sorting should be done at once by the collector, with the intelligent co-operation of the householder. Things dissimilar in nature should never be mixed. The first division is into putrescible and non-putrescible, and the former should be sent forthwith to the farmer to be dug into the ground. ”

“ But among land animals themselves there are very great differences of distribution, due to certain specialities in their organization or mode of life. These act mainly in two ways,—1stly, by affecting the facilities with which they can be dispersed, either voluntarily or involuntarily;—2ndly, by the conditions which enable them to multiply and establish themselves in certain areas and not in others. When both these means of diffusion are at a maximum, the dispersal of a group becomes universal, and ceases to have much interest for us. ”

“ Since every animal naturally tends to spread in every direction from its original home—that is to say, from the place of its origin—the latter should correspond with the centre of its range. And in any particular group of animals the maximum number of species should be formed in the area or zone which is the centre of its distribution. ”

“ Hence would come his conclusion that when, with human beings, are incorporated the less vitalized beings, animal and vegetal, covering the surface occupied by the society, an aggregate results having a continuity of parts, more nearly approaching to that of an individual organism, and which is also like it in being composed of local aggregations of highly-vitalized units, imbedded in a vast aggregation of units of various lower degrees of vitality, which are in a sense produced by, modified by, and arranged by, the higher units. ”

“ Geometrical analysis and synthesis are similar to logical division and definition; and by division we get back to what is simple and more elementary. We divide, therefore, the genus of what is proposed for consideration into the species contained in it; as, in the case of man, we divide animal, which is the genus, into the species that appear in it, the mortal, and the immortal. And thus, by continually dividing those genera that seem to be compound into the simpler species, we arrive at the point which is the subject of investigation, and which is incapable of further division. ”

“ We may assume that at the beginning of the present order of things, a stock of each species was placed in the vegetable or animal province to which it belongs, by some cause out of the common order of nature; or we may take a uniformitarian view of the subject, and suppose that the provinces of the organic world derived their population from some anterior state of things by the operation of natural causes. ”

“ Here an attempt has been made to remove the confusion; and it is believed that the associations of those two branches of Natural Science, in groupings arranged in such a [I-91] manner as the nature of the building will permit, coupled with illustrations of the human variety belonging to the same soil (a collection which has never before been attempted in any country) , will prove both instructive and amusing, and afford a clearer conception than can be obtained elsewhere of the manner in which the varieties of man, animals, and plants, are distributed over the globe. ”

“ We have, in this enumeration, a series of groups of strata, each of which, speaking in a general way, has its own population of animals and plants, and is separated, by the peculiarities of these, from the groups below and above it. Each group may, in a general manner, be considered as a separate creation of animal and vegetable forms—creatures which have lived and died, as the races now existing upon the earth live and die ”

“ Next to the mode of living, we are to consider ‘the quantity of provision suited to that mode, which is either raised in the country or imported into it,’ for this is the order in which we assigned the causes of population and undertook to treat of them. Now, if we measure the quantity of provision by the number of human bodies it will support in due health and vigour, this quantity, the extent and quality of the soil from which it is raised being given, will depend greatly upon the kind. ”

“ For, within the hive as well, they have their allotted duties to perform: some are engaged in building, others in smoothing the combs, while others again are occupied in passing on the materials, and others in preparing food from the provision which has been brought; that there may be no unequal division, either in their labor, their food, or the distribution of their time, they do not even feed separately. ”

“ When organisms, though distinguished from one another by some major difference, agree, notwithstanding, in the main elements of structure, the several species to which they belong are grouped under a common genus, and similarly genera are grouped into families. A relative major difference, such as a difference in the size of the teeth, suffices for the segregation of a new species, while an absolute difference, such as a difference in the number of teeth or the possession of an additional organ, suffices for the segregation of a new genus. ”

“ This will become evident when we consider that the importance of the possession of a group by one region depends on its absence from the adjoining regions; and if there is now no barrier to its entrance, we may be sure that there has once been one; and that the possession of the area by a distinct and well balanced set of organisms, which must have been slowly developed and adjusted, is the living barrier that now keeps out intruders. ”

“ But since the population of this imaginary area has reached the maximum, and the supply of food, though limited in distribution, is nevertheless plentiful, such movements will be irregular and will proceed in no definite direction. ”

“ Restricted Areas of Families.—As families sometimes consist of single genera and even single species, they often present examples of very restricted range; but what is perhaps more interesting are those cases in which a family contains numerous species and sometimes even several genera, and yet is confined to a narrow area. ”

“ When aggregating the smallest groups into larger groups and these into groups still larger, they have adopted certain general terms expressive of the successively more comprehensive divisions; and the habitual use of these terms, needful for purposes of convenience, has led to the tacit assumption that they answer to actualities in Nature. It has been taken for granted that species, genera, orders, and classes, are assemblages of definite values—that every genus is the equivalent of every other genus in respect of its degree of distinctness ”

“ In an environment which remained constant and where a species of animals had reached a population which strained the limits of subsistence—food supply—those offspring which most closely resemble their parents, who had won out in that environment, would again succeed and be selected. ”

“ Thus, without multiplying illustrations and without descending to genera and species, we see that, speaking generally, the successively smaller groups are distinguished from one another by traits of successively less importance, physiologically considered. The attributes possessed in common by the largest assemblages of organisms, are few in number but all-essential in kind. ”

“ The three sets of figures in the left-hand column indicate different positions of equilibrium in a population consisting of homozygous dominants, heterozygous dominants, and recessives. The remaining columns indicate the number of generations in which a population will pass from one position of equilibrium to another, under a given intensity of selection. ”

“ Yet a third group, recognizing the demand for wood, alike for agricultural and building purposes, will betake themselves to the adjacent forests. But in no case will the primary assemblage, before these separations, settle the arrangements and actions of each group: it will leave each group to settle them for itself. ”

“ In considering the distribution of species, we may also proceed, without regard to the multiplication of individuals, to the masses which they form or the space which they occupy, and may simply compare together the absolute number of species belonging to a particular family in each country. ”

“ Orders are groups of genera that resemble each other; that is, they are to genera what genera are to species. As familiar illustrations, the Oak, Chestnut, and Beech genera, along with the Hazel genus and the Hornbeams, all belong to one order. ”

“ Hence probably it is, that we feel so little surprise at one, of two species closely allied in habits, being rare and the other abundant in the same district; or, again, that one should be abundant in one district, and another, filling the same place in the economy of nature, should be abundant in a neighbouring district, differing very little in its conditions. ”

“ It occurs in species of wide range, when groups of individuals have become partially isolated in several points of its area of distribution, in each of which a characteristic form has become more or less completely segregated. Such forms are very common in all parts of the world, and have often been classed by one author as varieties, by another as species. ”

“ The higher and more complex the organization, the smaller the disproportion.
In fact, in the vegetables, each individual produces every year an infinite number of seeds, and an infinitesimal number of these survive. In the animals, the number of young of each individual diminishes and the number of those who survive continues on the con [Pg 36] trary, to increase. Finally, for the human species, the number of individuals that each one can beget is very small and most of them survive. ”

“ Each great center of production, each manufacturing town or district continues always in the same place; and many of the firms in such town or district are for generations carried on either by the descendants or successors of those who founded them. Just as in a living body, the cells that make up some important organ, severally perform their functions for a time and then disappear, leaving others to supply their places ”

“ That process of grouping which constitutes the first step towards the production of complex organisms, we shall now find repeated in the formation of series of groups. Just as a diminution of the separative tendency is shown in the aggregation of divided monads, so is a further diminution of it shown in the aggregation of the divided groups of monads. ”

“ In a population in equilibrium which contains about 2% of a dominant form, the great bulk of these dominants will be heterozygous, and the relative proportion of recessives, heterozygous, and homozygous dominants is given in the second line of the left-hand column. ”