1899] TREES IN WINTER 405 



winter rest of our trees is the lavish accumulation of oxalate of calcium 

 in the buds and even in the pith of the young shoots. A section 

 made even in October through the bud of sycamore, alder, or ash 

 reveals an extraordinary state of affairs. What does it all mean ? 

 The cells seem reeking, as it were, with large or small crystals well and 

 truly formed. In sycamore buds these are very large, while in those 

 of the ash they are of all sizes apparently. A transverse section of 

 the bud-scales of the latter tree shows a peculiar collenchymatous tissue 

 filled with a thickly granulated plasma which invariably encloses 

 among several tiny rodlets of oxalate of calcium, a large octahedron of 

 the same substance. " The oxalate formed in the autumn in the buds 

 is still unchanged in spring," says Wehmer. Kraus concludes that it 

 is a reserve food material and not an excretion, and is taken up in 

 spring ; but after careful study and consideration I am disposed to 

 conclude that it merely represents an oxidation product of the 

 carbohydrates ; in fact, it is the result of a specially active metabolism 

 connected with the molecular rearrangement of certain carbohydrates 

 while being subjected to an unwonted and extraordinary intensity of 

 respiration. 



Patterdale, Westmorland. 



