Origin of Species Variorum

→ modification — Absence 1872

modification — Transitions — Absence 1859 1860 1861 1869

modification—Transitions—Absence 1866

→ varieties — Transitions 1859 1860 1861 1869 1872

varieties—Transitions 1866

→ life — Diversified 1859 1860 1861 1869 1872

life—Diversified 1866

→ species — Species 1859 1860 1861 1869 1872

species—Species 1866

→ allies — Organs 1859 1860 1861 1869 1872

allies—Organs 1866

→ perfection — Modes 1869 1872

perfection — Means 1859 1860 1861

perfection—Modes 1866

→ transition — Cases 1859 1860 1861 1869 1872

transition—Cases 1866

→ difficulty — Natura 1859 1860 1861 1869 1872

difficulty—Natura 1866

→ saltum — Organs 1859 1860 1861 1869 1872

saltum—Organs 1866

→ importance — Organs 1859 1860 1861 1869 1872

importance—Organs 1866

→ perfect — The 1859 1860 1861 1869 1872

perfect—The 1866

→ the reader has 1872

having 1859 1860 1861 1866 1869

→ in some degree staggered; 1872

staggered; 1859 1860 1861 1866 1869

→ other animal with widely different 1872

animal with wholly different 1859 1860 1861 1866

animal with widely-different 1869

→ habits and structure? 1872

habits? 1859 1860 1861 1866

structure and habits? 1869

→ an organ so wonderful 1872

organs of such wonderful structure, 1859 1860 1861 1866 1869

→ the instinct 1872

so marvellous an instinct as that 1859 1860 1861 1866 1869

→ and which has 1872

which have 1859

which has 1860 1861 1866 1869

→ will here be discussed; some miscellaneous objections in the following chapter; Instinct 1872

shall be here discussed— Instinct 1859 1860 1861

shall be here discussed—Instinct 1866 1869

CHAPTER VI.

DIFFICULTIES

OF THE

THEORY.

Difficulties

the theory of descent with →modification — Absence or rarity of transitional →varieties — Transitions in habits of →life — Diversified habits in the same →species — Species with habits widely different from those of their →allies — Organs of extreme →perfection — Modes of →transition — Cases of →difficulty — Natura non facit →saltum — Organs of small →importance — Organs not in all cases absolutely →perfect — The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection.

LONG before →the reader has arrived at this part of my work, a crowd of difficulties will have occurred to

the reader.

him.

Some of them are so

grave

serious

that to this day I can

never

hardly

reflect on them without being →in some degree staggered; but, to the best of my judgment, the

greater

....

number are only apparent, and those that are real are

not,

greater not,

I think, fatal to

the

theory.

These difficulties and objections may be classed under the following

heads:— Firstly,

heads:—Firstly,

heads:—First,

heads:— First,

why, if species have descended from other species by

insensibly

....

fine gradations, do we not everywhere see innumerable transitional forms? Why is not all nature in

confusion

confusion,

instead of the species being, as we see them, well defined?

Secondly, is it possible that an animal having, for instance, the structure and habits of a bat, could have been formed by the modification of some →other animal with widely different →habits and structure? Can we believe that natural selection could produce, on the one hand,

organs

an organ

of trifling importance, such as the tail of a giraffe, which serves as a fly-flapper, and, on the other hand, →an organ so wonderful as the

eye,

which

hardly

yet

fully

understand

the

inimitable

perfection?

Thirdly, can instincts be acquired and modified through natural selection? What shall we say to →the instinct which leads the bee to make cells, →and which has practically anticipated the discoveries of profound mathematicians?

Fourthly, how can we account for species, when crossed, being sterile and producing sterile offspring, whereas, when varieties are crossed, their fertility is unimpaired?

The two first heads →will here be discussed; some miscellaneous objections in the following chapter; Instinct and