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. 
