14-6 Mr. Winch's Observations on his Flora. 



towards the north. Their appearance on this side of the Tees is partly 

 owing to the shelter afforded by the Cleveland hills, but more especially 

 by the warm and fertile soil originating from the decomposition of the 

 Red Sandstone rocks, prevalent in the lower part of this vale. 



On referring to the latter pages of this Catalogue, it will readily be 

 seen how greatly its numbers have been increased by the assiduity of 

 Dr. G. Johnston, author of the Berwick Flora,* who has shown how 

 much may be learned respecting the most minute cryptogamic produc- 

 tions, by a diligent use of the microscope, and by a fixed determination 

 to follow up a peculiar line of study and investigation. 



To my other numerous friends, who have favoured me with speci- 

 mens or delineations of plants, I beg leave to acknowledge the kindness 

 conferred, and whenever the name of a correspondent is attached to a 

 locality, thanks for the communication are to be implied as a matter of 

 course. 



* A Flora of Benvick iipoyi Tweed, by G. Johnston, M. D. 2 vols. 12mo., Edinburgh, 

 1829 and 1831. 



