1888.] NATURAL SCIENCES OF rillLADELPHIA. G9' 



In 1855 he made his third journey, visiting some of his old friends 

 but remaining from home but six Meeks. His fourth trip to Enghmd 

 and the Continent ^vas made in 1868. Between the years 1856, the 

 date of the hist visit, and 1868 much valuable work had been done. 

 He had issued his "Structural and Morphological Botany" which had 

 no rival in America, and no superior in Europe. It was a model 

 of clearness and conciseness in its methods of treating the general 

 morphology of the plant and especially that of the flower. 



The "Manual" had been published and was already recognized as 

 worthy a place by the side of Koch's German Flora. No higher praise 

 could have been given to it. The two JManuals were regarded as 

 models of clearness and brevity in description. 



The work, also that on the Flora of North America, had been con- 

 stantly carried on, besides the jDublication of various papers on botan- 

 ical subjects, the most important of which was: "Relation of the 

 Japanese Flora to that of North America." This had been a very 

 remarkable piece of work, requiring close reasoning and comj^arisou, 

 all the more remarkable because the geological and palaeontological 

 work on the fossil flora of the North by Heer had then not been 

 done. The "Principles of Variation in Species" soon to be made 

 known by Charles Darwin's " Origin of Species " was yet unpub- 

 lished. Both of these works might have given great help toward 

 the solution of the problem in hand. It is safe to say that this last 

 work made him known to every active thinker in Europe. 



What wonder is it then, that after the very successful issue of his 

 valuable text-books, after many additions to the North American 

 Flora and the publication of numerous papers including the last one 

 mentioned on geographical distribution, this fourth visit abroad in 

 1868, should have been one continued ovation? Leaving home in 

 September he spent this and the following autumn at Kew, hard at 

 work. In the interim, visiting Paris, he renewed old acquaintances ; 

 worked with von Martius in JNIunich and with DeCandolle in Geneva, 

 and visited various herbaria all over the Continent before returning 

 to England. 



So:nething of the high regard in which his scientific labors were 

 held at this time may be gathered from the fact that when he sailed 

 for home in 1869 he had been made a member of nearly every Royal 

 Scientific Society in Europe. 



He was in Europe twice after this ; first in 1880, remaining about 

 a year. He visited Paris, the Herbarium at Madrid, Spain, most of 



