Numerous instances could be given of characters derived from parts which must be considered of very trifling physiological importance, but which are universally admitted as highly serviceable in the definition of whole groups. For instance, whether or not there is an open passage from the nostrils to the mouth, the only character, according to Owen, which absolutely distinguishes fishes and reptiles— the inflection of the angle of the
jaws jaws 1859 1860 1861 1866 1869 | lower jaw 1872 |
in Marsupials— the manner in which the wings of insects are folded— mere colour in certain Algæ— mere pubescence on parts of the flower in grasses— the nature of the dermal covering, as hair or feathers, in the Vertebrata. If the Ornithorhynchus had been covered with feathers instead of hair, this external and trifling character would,
I think,
have been considered by naturalists as
an aid as important an aid as important 1866 |
important an aid 1859 1860 1861 |
an important aid 1869 1872 |
in determining the degree of affinity of this strange creature to
birds birds 1859 1860 1861 1866 | birds. 1869 1872 |
and and 1859 1860 1861 1866 | and 1869 1872 |
reptiles, reptiles, 1859 1860 1861 1866 | reptiles, 1869 1872 |
as as 1859 1860 1861 1866 | as 1869 1872 |
an an 1859 1860 1861 1866 | an 1869 1872 |
approach approach 1859 1860 1861 1866 | approach 1869 1872 |
in in 1859 1860 1861 1866 | in 1869 1872 |
structure structure 1859 1860 1861 1866 | structure 1869 1872 |
in in 1859 1860 1861 1866 | in 1869 1872 |
any any 1859 1860 1861 1866 | any 1869 1872 |
one one 1859 1860 1861 1866 | one 1869 1872 |
internal internal 1859 1860 1861 1866 | internal 1869 1872 |
....... 1861 1866 | OMIT 1869 1872 | and important 1859 1860 |
organ. organ. 1859 1860 1861 1866 | organ. 1869 1872 |
|
The importance, for classification, of trifling characters, mainly depends on their being correlated with
several several 1859 1860 1861 1866 1869 | many 1872 |
other characters of more or less importance. The value indeed of an aggregate of characters is very evident in natural history. Hence, as has often been remarked, a species may depart from its allies in several characters, both of high physiological
importance importance 1859 1860 1861 1866 1869 | importance, 1872 |
and of almost universal prevalence, and yet leave us in no doubt where it should be ranked. Hence, also, it has been
found, found, 1859 1860 1861 1866 | found 1869 1872 |
that a classification founded on any single character, however important that may be, has always failed; for no part of the organisation is
universally universally 1859 1860 1861 1866 | invariably 1869 1872 |
constant. The importance of an aggregate of characters, even when none are important, alone
explains, explains, 1859 1860 1861 1866 | explains 1869 1872 |
I think, that saying by Linnæus, I think, that saying by Linnæus, 1866 |
I think, that saying of Linnæus, 1859 1860 1861 |
the aphorism by Linnæus, namely, 1869 |
the aphorism enunciated by Linnæus, namely, 1872 |
that the characters do not give the genus, but the genus gives the characters; for this
saying saying 1859 1860 1861 1866 | saying 1869 1872 |
seems founded on
an an 1859 1860 1861 1866 1869 | the 1872 |
appreciation of many trifling points of resemblance, too slight to be defined. Certain plants, belonging to the Malpighiaceæ, bear perfect and degraded flowers; in the latter, as A. de Jussieu has remarked, "the greater number of the characters proper to the species, to the genus, to the family, to the class, disappear, and thus laugh at our classification."
But But 1859 1860 1861 1866 1869 | But 1872 |
when when 1859 1860 1861 1866 1869 | When 1872 |
Aspicarpa produced in France, during several years, only
degraded degraded 1859 1860 1861 1866 1869 | these degraded 1872 |
flowers, departing so wonderfully in a number of the most important points of structure from the proper type of the order, yet M. Richard sagaciously saw, as Jussieu observes, that this genus should still be retained amongst the Malpighiaceæ. This case
seems to me well to seems to me well to 1859 1860 1861 1866 1869 |
well 1872 |
illustrate illustrate 1859 1860 1861 1866 1869 | illustrates 1872 |
the spirit
with which with which 1859 1860 1861 1866 | of 1869 1872 |
our
classifications classifications 1859 1860 1861 1866 | classifications. 1869 1872 |
are are 1859 1860 1861 1866 | are 1869 1872 |
sometimes sometimes 1859 1860 1861 1866 | sometimes 1869 1872 |
necessarily necessarily 1859 1860 1861 1866 | necessarily 1869 1872 |
founded. founded. 1859 1860 1861 1866 | founded. 1869 1872 |
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