| → between the several islets of these small archipelagos, 1869 1872 |
| Ireland, 1859 1860 1861 |
| between the several islets in each of these small archipelagos, 1866 |
|
| ↑ 1 blocks not present in 1859 1860 1866 1869 1872; present in 1861 |
| Some few naturalists maintain that animals never present varieties; but then these same naturalists rank the slightest differences as of specific value; and when even the same identical form is met with in two distant countries, or in two quite distinct geological formations, they go so far as to believe that two separate species are hidden under the same dress.
|
|
| → described what he calls Phytophagic varieties and Phytophagic species. 1869 |
| called attention to some cases, analogous with those of local forms and geographical races, yet very different from them. 1866 |
|
| → to be thus affected 1869 |
| thus to differ 1872 |
|
| → determine for others, 1869 |
| draw the line for others, 1866 |
| determine for another, 1872 |
|
| → OMIT 1869 1872 |
| and determine with certainly 1866 |
|
| → ought to be called species 1869 1872 |
| to call varieties 1866 |
|
| → varieties. 1869 1872 |
| to call species. 1866 |
|
|
has a few animals, now generally regarded as varieties, but which have been ranked as species by some zoologists. Several
experienced ornithologists consider our British red grouse as only a strongly-marked race of a Norwegian species, whereas the greater number rank it as an undoubted species peculiar to Great Britain. A wide distance between the homes of two doubtful forms leads many naturalists to rank
as distinct species; but what distance, it has been well asked, will
that between America and Europe is ample, will that between
and the Azores, or Madeira, or the Canaries, or
→between the several islets of these small archipelagos,
be sufficient? ↑ |
|
| Mr. B. D. Walsh, a distinguished entomologist of the United States, has lately
→described what he calls Phytophagic varieties and Phytophagic species.
Most vegetable-feeding insects live on one kind of plant or on one group of plants;
some feed indiscriminately on many
kinds,
but do not in consequence vary.
In several cases, however, insects found living on different
have been observed by Mr. Walsh to
in their larval or mature state, or in both states, slight, though constant differences in colour, size, or in the nature of their secretions. In some instances the males alone, in other instances both males and females, have been observed
→to be thus affected
in a slight degree. When the differences are rather more strongly marked, and when both sexes and all ages are affected, the forms
ranked by all entomologists as
But no
can
→determine for others,
even if he can do so for himself,
→OMIT
which of
forms
→ought to be called species
and which
→varieties.
Mr. Walsh ranks the forms which it may be supposed would freely
as varieties; and those which appear to have lost this power, as
|
