Book,  Paragraph

 1   I,  1 |           that of plants, have no sex any more than plants have,
 2   I,  2 |          then, the distinction of sex is a first principle; at
 3   I,  18|      there is a difficulty if the sex is determined in conception (
 4   I,  18|         being so, that the female sex is not determined by the
 5   I,  19| generative power fails in the one sex and the catamenia in the
 6   I,  20|        the active and the passive sex must also differ. If, then,
 7  II,  8 |   generate, both because the male sex is naturally hotter than
 8 III,  1 |          due to any difference of sex, as if the white came from
 9 III,  5 |           kind the distinction of sex does not exist), and without
10 III,  7 |            there had been no male sex in the class of birds, the
11 III,  10|          female in which the male sex is not separated. But if
12  IV,  1 |       that the differentiation of sex takes place within the mother;
13  IV,  1 |          to the production of one sex rather than the other; a
14  IV,  1 |          which the distinction of sex exists, and which produce
15  IV,  1 |   analogue. Now since (1) the one sex is able and the other is
16  IV,  3 |          assign the same cause of sex as Empedocles or Democritus
17  IV,  3 |             1) the distinction of sex, (2) why the female is often