A difficulty may be raised concerning (1) the production of many
young and the multiplication of the parts in a single young one, and
(2) the production of few young or only one and the deficiency of
the parts. Sometimes animals are born with too many toes, sometimes
with one alone, and so on with the other parts, for they may be
multiplied or they may be absent. Again, they may have the
generative parts doubled, the one being male, the other female; this
is known in men and especially in goats. For what are called
'tragaenae' are such because they have both male and female generative
parts; there is a case also of a goat being born with a horn upon
its leg. Changes and deficiencies are found also in the internal
parts, animals either not possessing some at all, or possessing them
in a rudimentary condition, or too numerous or in the wrong place.
No animal, indeed, has ever been born without a heart, but they are
born without a spleen or with two spleens or with one kidney; there is
no case again of total absence of the liver, but there are cases of
its being incomplete. And all these phenomena have been seen in
animals perfect and alive. Animals also which naturally have a
gall-bladder are found without one; others are found to have more than
one. Cases are known, too, of the organs changing places, the liver
being on the left, the spleen on the right. These phenomena have
been observed, as stated above, in animals whose growth is
perfected; at the time of birth great confusion of every kind has been
found.
Pages:
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198