OUTLINE OF BIOLOGICAL PROGRESS 13 
the scientific writings ascribed to Aristotle were all from his 
hand. The work is so uneven that Huxley has suggested 
that, since the ancient philosophers taught viva vece, what 
we have of his zodlogical writings may possibly be the notes 
of some of his students. While this is not known to be the 
case, that hypothesis enables us to understand the intimate 
mixture of profound observation with trivial matter and 
obvious errors that occur in the writings ascribed to him. 
Hertwig says: “It is a matter for great regret that there 
have been preserved only parts of his three most important 
zodlogical works, ‘ Historia animalium, ‘De partibus,’ and 
‘De generatione, works in which zoédlogy is founded as a 
universal science, since anatomy and embryology, physiology 
and classification, find equal consideration.” 
Some Errors.—Dissections were little practised in his 
day, and it must be admitted that his observations embrace 
many errors. He supposed the brain to be bloodless, the 
arteries to carry air, etc., but he has been cleared by Huxley 
of the mistake so often attributed to him of supposing the 
heart of mammals to have only three chambers. It is alto- 
gether probable that he is credited with a larger number of 
errors than is justified by the facts. 
He must have had unusual gifts in the exposition of these 
technical subjects; indeed, he made his researches appear 
so important to his royal patron, Alexander, that he was 
aided in the preparation of his great Natural History by a 
grant of 800 talents (equivalent to $200,000) and by nu- 
merous assistants and collectors. Thus in ancient times was 
anticipated the question that is being agitated to-day—that 
of the support and the endowment of research. 
Personal Appearance.—Some idea of his looks may be 
gained from Fig. 1. This is a copy of a bas-relief found in 
the collection of Fulvius Ursinus (d. 1600), and was originally 
published by J. Faber. Its authenticity as a portrait is 
