Vallisneri, Antonio. Istoria della generazione dell’uomo, e degli animali, se sia da’ vermicelli spermatici o dalle uova. Venezia, Giovanni Gabriele Hertz, 1721.
25 x 18 cm
13 plates engraved in copper and folded at the end of the volume. Half leather binding with title on the spine.
Antonio Vallisneri (1661–1730
Vallisneri, professor in Padua of Practical Medicine and subsequently Theoretical Medicine, distinguished himself for his studies in the field of human pathology, supported by comparative naturalistic and anatomical studies as a basis for medical studies. He observed several cases of monstrosities and theorized that conjoined twins were born “from two germs or mature eggs, which, by matching closely, over time attack and interpenetrate, so that they compose a doubled body. This seems evident in the hen‘s eggs, which have two or more yolks, from which chickens with two or more heads, or with multiplied limbs, are born. Instead, the twins are born separated, when the eggs are separated in the trumpets, so they descend in the same way into the matrix and each has its own placenta, its umbilical vessels and its enveloping membranes”.