152 JOHN STEVENS HENSLOW 



Dr Leach, at Baitsbite on the Cam. His first and best collec- 

 tion of insects was presented to the Cambridge Philosophical 

 Society. Other discoveries were made in after years, and are 

 referred to by Jenyns. 



On the death of Dr E. D. Clarke, he offered himself for the 

 Professorship of Mineralogy. Chemistry, as well as the study of 

 Minerals, now occupied his attention. He was only 26 years of 

 age, and still B.A., when elected to that chair. At the age of 

 27 he published his Syllabus of Mineralogy in 1823, "A useful 

 manual of reference to all persons studying Mineralogy, in- 

 dependently of the immediate circumstances which led to its 

 publication 1 ." 



In 1827 Prof. Martyn died and Prof. Henslow was elected to 

 the chair of Botany, being succeeded by Whewell on resigning 

 the Professorship of Mineralogy. He now turned his attention 

 to the study of Botany ; but he never paid much heed to 

 systematic botany, for his taste lay in the direction of what 

 is now called Ecology. He then wrote " Botanists would 

 rather receive one of our most common weeds from a newly- 

 discovered or newly-explored country, than a new species of 

 an already known genus. There are higher departments of 

 Botany than mere collectors of specimens are aware of; for to 

 ascertain the geographical distribution of a well-known species 

 is a point of vastly superior interest to the mere acquisition of 

 a rare specimen." A propos of this he made elaborate epitomes 

 of the Botanical Geographies of De Candolle, and of the writings 

 of Humboldt, Poiret and others. His MS. is not unlike a fore- 

 runner of Schimper's Botanical Geography of to-day. He thus 

 expressed himself in the Introduction to his Descriptive and 

 Physiological Botany (1836): in the second section headed 

 Botany... 11 This enquiry should extend as well to the investi- 

 gation of the outward forms [of plant organs] and the conditions 

 in which plants, whether recent or fossil, are met with, as to 

 the examination of the various functions which they perform 

 whilst in the living state and to the laws by which their distri- 

 bution on the earth's surface is regulated." Again, in the 

 Preface to the Flora of Suffolk by himself and E. S. Skepper, 



1 Memoir, p. 29. 



