1 6 Botanists of Germany and the Netherlands [BOOK i. 



physicians \ they were compelled to compare together a great 

 variety of native plants, and thus to exercise and perfect the 

 faculty of apprehending differences of form. This mode of 

 proceeding, arising out of medical requirements, directed the 

 attention entirely to the individual form, which was also the 

 chief thing required in the interest of pure science, and much 

 more was thus gained than if these men had only followed the 

 philosophical writings of Aristotle a and Theophrastus 3 . The 

 Greek authors built their views on the philosophy of botany on 

 very weak foundations ; scarcely a plant was known to them 

 exactly in all its parts ; they derived much of their knowledge 

 from the accounts of others, often from dealers in herbs. From 

 this scanty material and from various popular superstitions had 

 Aristotle formed his views on the nature of plants, and if 

 Theophrastus possessed more experimental knowledge, he still 

 saw facts in the light of his master's philosophical doctrines. 

 If we succeed in the present day in extracting much that is 

 accurate from the writings of Aristotle and Theophrastus, it was 

 nevertheless well that the first compilers of herbals ceased to 

 pay attention to them, and occupied themselves with accumu- 

 lating desrciptions of individual plants worked out by them- 



1 Beside the herbals mentioned in the text, which may be regarded as 

 scientific works on botany, a considerable number of books on the signature 

 of plants were written in the i6th and i7th centuries in the interests of 

 medicine or medical superstition. It was believed that certain external 

 marks and resemblances between parts of plants and the organs of the 

 human body indicated the plants and the parts of them which possessed 

 healing virtues. Pritzel mentions by name twenty-four works of the kind, 

 which appeared between 1550 and 1697. The herbals also noticed the sig- 

 natures, and even Ray has an enquiry into the subject. 



a The fragments of Aristotelian botany which have come down to us are 

 to be found translated from Wimmer's edition in Ernst Meyer's ' Geschichte 

 der Botanik,' i. p. 94. 



3 Ernst Meyer (Geschichte der Botanik) gives a full account of Theo- 

 phrastus, who was born at Lesbos A.c. 371 and died A.c. 286. An edition 

 of his work ' De historia et de causis plantamm ' was published by Theodor 

 Gaza in 1483. See also Pritzel's ' Thesaurus literarum botanicarum.' 



