258 WILLIAM CRAWFORD WILLIAMSON 



who makes the honourable boast that he knew Williamson's 

 collection as no one else did. 



Williamson's writings are not easy reading, especially for the 

 modern botanical student, for the terminology is often unfamiliar, 

 and the arrangement of the matter unsystematic. 



It would be out of place to enter on a criticism of details, 

 but it is necessary to call attention to the one serious mistake 

 which ran through much of Williamson's work, though at the 

 last he to a great extent corrected it himself. He was always 

 too ready to interpret specimens of the same fossil plant which 

 differed in size and anatomical complexity, as developmental 

 stages of one and the same organ. Such differences among 

 fossils are more often due to the order of the branch on the 

 plant, or to the level at which a section is cut. This error led 

 to some mistaken, and indeed impossible views of the process of 

 development. I mention this partly because I have noticed the 

 same fundamental mistake in the work of much more modern 

 writers. "We are none of us infallible not even the youngest 

 of us," and among the latest fossil-botany papers I have read, 

 I have detected the very same confusion between differences 

 of size and differences of age, which constitutes the most serious 

 blemish in Williamson's writings. 



As is well known, Williamson in his latest independent work 

 corrected, as regards the Lepidodendrons, on the basis of a 

 laborious re-investigation, the chief mistake he had made as 

 to their process of growth 1 ; he thus displayed an openness 

 of mind worthy of a great naturalist. 



I first saw Williamson on February 16, 1883, when I 

 attended his Friday evening lecture at the Royal Institution, 

 "On some anomalous Oolitic and Palaeozoic Forms of Vege- 

 tation." I did not, however, make his acquaintance till six 

 years later, when we met at the British Association Meeting at 

 Newcastle-upon-Tyne, in 1889. This led to a visit to his house 

 in company with Prof. Bower; it was on March 8, 1890, that 



1 Williamson, " On the light thrown upon the question of the Growth and 

 Development of the Carboniferous Arborescent Lepidodendra by a study of the 

 details of their Organisation." Mem. and Proc. Manchester Lit. and Phil. Soc. y 

 Ser. iv. Vol. ix. 1895. 



