Harold Henry Welch Pearson. 



Ixi 



him. In 1916 he was elected a Fellow of the Koyal Society. On hearing 

 of his election, he wrote : — " I was a little surprised to find myself in the 

 list this year ; that I was pleased needs no statement. Under any circum- 

 stances I should appreciate the honour immensely ; under my particular 

 circumstances I think I value it more than I should have done under some 

 others — isolated here from the centre of the things that interest me, this 

 distinction means a very great deal to me." 



Pearson's first paper, published in the 'Annals of Botany' in 1898, deals 

 with the anatomy of seedlings of the Queensland Cycad Bowenia spedabilis 

 and includes a description of the apogeotropic roots of both young and adult 

 plants. Though he did not publish much on the Cycadacese, Pearson 

 made several important additions to our knowledge of this exceptionally 

 interesting family, notably through his own observations in the field and the 

 more continuous records kept at his suggestion by residents in the Cycad 

 country. He obtained convincing evidence of entomophily in Encephalartos 

 villosus, and in many other directions added to the meagre information 

 available with regard to the ecology and natural history of African Cycads. 

 He always had a special affection for Cycads, and was justly proud of the 

 splendid collection of living plants cultivated under his supervision in the 

 Kirstenbosch Garden. In 1897, aided by a grant from the University Worts 

 Travelling Fund, Pearson left Cambridge for Ceylon. The comparatively 

 short time spent in the island was mainly devoted to the investigation of 

 the Patanas, a peculiar savannah-like vegetation in the central mountain 

 group at approximately all altitudes over 2000 feet. At the suggestion of 

 Dr. J. C. Willis, then Director of the Peradeniya Gardens, Pearson undertook 

 the task of discovering the causes which led to the development of the 

 patanas, and of ascertaining to what extent the vegetation showed adapta- 

 tion to the ecological factors under the influence of which it had been 

 selected. He came to the conclusion that the peculiarities of the climate 

 have co-operated with periodically recurrent grass-fires in transforming an 

 open forest into barren grassy plains ; he made observations on the biological 

 features of the flora, and discussed the factors concerned with the production 

 of both wet and dry patanas, that is the vegetation above and below 

 4500 feet. In the investigation of the anatomy of the vegetative organs 

 he obtained the assistance of his friend Mr. J. Parkin. It was expected that 

 the anatomical characters which usually occur in plants living in insolated 

 areas would be more strongly marked in the members of the dry flora than 

 in the plants of the wet patanas, but it was found that the latter exhibited 

 highly developed xerophilous features. The dwarfing effect of the wind was 

 recognised as an important influence and emphasis was laid on the lowering 

 of the functional activity of the roots by the humic acids in the soil. 



Pearson's early training was exceptionally good as a preparation for his 

 later activities at the Cape. Familiar with modern laboratory methods, 

 he was also a capable field botanist, and at Kew he learnt the business of a 

 systematist. His broad outlook, his wide knowledge of botanical literature, 



