The Foundations of the Origin of Species Two Essays written in 1842 and 1844
CHAPTER IV 133-143
ON THE NUMBER OF INTERMEDIATE FORMS REQUIRED ON THE THEORY OF COMMON DESCENT; AND ON THEIR ABSENCE IN A FOSSIL STATE
The Foundations of the Origin of Species Two Essays written in 1842 and 1844
ON THE NUMBER OF INTERMEDIATE FORMS REQUIRED ON THE THEORY OF COMMON DESCENT; AND ON THEIR ABSENCE IN A FOSSIL STATE