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14 rows, page 4 of 4 (4/p)
1 2 3 4

Export to Excel select * from OriginOfSpecies where ordinal = '90' order by ordinal limit 12, 4 (Page 4: Row)
subject
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ordinal Desending Order (top row is first)
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13 - Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Or 13-03 - Rules and difficulties in classification, explained on the theory of descent with modification 90 The same fact holds good with flowering plants, of which the two main divisions have been founded on characters derived from the embryo, on the number and position of the embryonic leaves or cotyledons, and on the mode of development of the plumule and radicle.

In our discussion on embryology, we shall see why such characters are so valuable, on the view of classification tacitly including the idea of descent.

Our classifications are often plainly influenced by chains of affinities.

Nothing can be easier than to define a number of characters common to all birds; but in the case of crustaceans, such definition has hitherto been found impossible.

bird
bird

crustacean
crustacean


There are crustaceans at the opposite ends of the series, which have hardly a character in common; yet the species at both ends, from being plainly allied to others, and these to others, and so onwards, can be recognised as unequivocally belonging to this, and to no other class of the Articulata.
12 - Geographical Distribution -- continued 12-50 - On colonisation from the nearest source with subsequent modification 90 I can hardly doubt that this rule is generally true, though it would be difficult to prove it.

Amongst mammals, we see it strikingly displayed in Bats, and in a lesser degree in the Felidae and Canidae.

bat
bat

cat
cat

dog
dog


We see it, if we compare the distribution of butterflies and beetles.

butterfly
butterfly

beetle
beetle