Antonii a Leeuwenhoek ... Epistolae physiologicae super compluribus naturae arcanis

LETTER XXX. Page 287

Conception does not occur by means of an egg. Concerning the animalcules of the masculine seed. The milt of the haddock abounds with countless animalcules. The seminal animalcules, in the larger and smaller species of fish, are of equal size. Those animalcules are not worms, devoid of life, etc. The animalcules appear to differ in sex. Generation, as it occurs by means of an egg, is effectively refuted. Certain other things concerning seminal animalcules.

LETTER XXXI. Page 301

ON the animalcules of ram's seed original: "femenis Arietini". The huge multitude of them. The capacity and description of the deferent vessel. The parastatae original: "Parastatae" epididymides of a ram dissected, and animalcules found in their humor. Adult and non-adult animalcules. The vessel commonly called the deferent does not appear to truly be a deferent vessel. More concerning the epididymides, the deferent vessel, the testicles, etc.

LETTER XXXII. Page 309

Nerves cut out from the spinal marrow of cows and sheep, and examined. One small nerve is woven from a hundred vessels. The cavities of the nerves, and indeed the parts included in the cavities, observed by the Author. The vessels of the spinal marrow are also passable through hollow passages. Various things concerning nerves, and their propagation from the spinal marrow. The cavities of the nerves observed more distinctly.