GREEK BIOLOGY AND MEDICINE 



Aristotle's orders of animals, I quote the criti- 

 cal resume of a recent authority: 



" The classification of birds is to this day 

 in an unstable state. We may say that Aris- 

 totle's grouping is substantially that which pre- 

 vailed in scientific works till recent times and 

 still remains as the popular division. His 

 separation of the cartilaginous from the bony 

 fishes, on the other hand, still stands in scien- 

 tific works, and is a stroke of genius which 

 must have been reached by means of careful 

 dissection. . . . 



" For the Anaima [bloodless] or Inverte- 

 brates even modern systems of classification 

 are but tentative. There is an enormous num- 

 ber of species, and after centuries of research 

 naturalists still find vast gaps even in the field 

 of mere naked-eye observation. Nevertheless, 

 with the instinct of genius, and with only 

 some 240 of these forms on which to work, 

 Aristotle has fastened on some of the most 

 salient points. Especially brilliant is his treat- 

 ment of the Molluscs. There can be no doubt 

 that he dissected the bodies and carefully 

 watched the habits of octopuses and squids, 

 Malaria as he calls them. He separates them 

 too far from the other Molluscs grouped by 

 [60] 



