Fossil Monkeys 127 



apes. Let us consider for a little the more essential additions to our 

 knowledge since the publication of The Descent of Man. 



Since that time our knowledge of animal embryos has increased 

 enormously. While Darwin was obliged to content himself with 

 comparing a human embryo with that of a dog, there are now avail- 

 able the youngest embryos of monkeys of all possible groups (Orang, 

 Gibbon, Semnopithecus, Macacus), thanks to Selenka's most successful 

 tour in the East Indies in search of such material. We can now compare 

 corresponding stages of the lower monkeys and of the Anthropoid 

 apes with human embryos, and convince ourselves of their great 

 resemblance to one another, thus strengthening enormously the 

 armour prepared by Darwin in defence of his view on man's nearest 

 relatives. It may be said that Selenka's material fills up the blanks 

 in Darwin's array of proofs in the most satisfactory manner. 



The deepening of our knowledge of comparative anatomy also 

 gives us much surer foundations than those on which Darwin was 

 obliged to build. Just of late there have been many workers in the 

 domain of the anatomy of apes and lemurs, and their investigations 

 extend to the most different organs. Our knowledge of fossil apes 

 and lemurs has also become much wider and more exact since 

 Darwin's time : the fossil lemurs have been especially worked up 

 by Cope, Forsyth Major, Ameghino, and others. Darwin knew very 

 little about fossil monkeys. He mentions two or three anthropoid apes 

 as occurring in the Miocene of Europe 1 , but only names Dryopiihecus, 

 the largest form from the Miocene of France. It was erroneously 

 supposed that this form was related to Hylobates. We now know 

 not only a form that actually stands near to the gibbon (Pliopi- 

 thecus), and remains of other anthropoids (Pliohylobates and the 

 fossil chimpanzee, Palaeopithecus), but also several lower catarrhine 

 monkeys, of which Mesopithecus, a form nearly related to the modern 

 Sacred Monkeys (a species of Semnopithecus) and found in strata of the 

 Miocene period in Greece, is the most important. Quite recently, too, 

 Ameghino's investigations have made us acquainted with fossil monkeys 

 from South America {Anthropops, Homunculus), which, according to 

 their discoverer, are to be regarded as in the line of human descent. 



What Darwin missed most of all — intermediate forms between 

 apes and man — has been recently furnished. E. Dubois, as is well 

 known, discovered in 1893, near Trinil in Java, in the alluvial 

 deposits of the river Bengawan, an important form represented by 

 a skull-cap, some molars, and a femur. His opinion — much disputed 

 as it has been — that in this form, which he named Pithecanthropus, 

 he has found a long-desired transition-form is shared by the present 

 writer. And although the geological age of these fossils, which, 



1 Descent of Man, p. 240. 



