86 
Field Notes. 
no starch, suggest that the abscissed twigs are exhausted of 
all food reserves. 
On the reproductive branches for year after year all but 
the terminal bud are catkin bearing. The production of 
catkins involves the utilisation of food stores in the branch and 
as such buds consist only of bud scales and a male catkin which 
sheds pollen and then falls, their formation is merely a drain 
on the supplies in the shoot. The terminal bud of the branch 
alone produces leaves to replenish these supplies, so that year 
after year all the activities of the branch, including the pro- 
duction of new catkins, the new extension growth of the shoot 
and the annual girth increase right down the branch, are 
supplied by the food materials made by the few leaves from 
this bud. It is only natural that the extension growth of 
the shoot should get less and less, the longer the branch has 
been flowering and also that, as the branch gets longer, the 
vigour of cambial activity reaching the base of the branch 
should become more and more feeble as the food supplies 
become depleted. The parenchymatous zone, which replaces 
the typical vascular tissues in the basal region, constitutes a 
position of weakness which is eventually unable to support the 
strains to which the branch is subjected and abscission’ results. 
References — 
1. Biisgen, M. The Structure and Life of Forest Trees, London, 1929. 
2. Eames, A. J. and Mac Daniels, L. H. An Introduction to Plant 
Anatomy, New York, 1925. 
3. Priestley, J. H. Studies in the Physiology of Cambial Activity III. 
New Phytologist, Vol. 29, pp. 316-354, 1930. 
4. Priestley, J . H. The Growing Tree. Presidential Address. Section 
K. Brit. Assoc., York, 1932. 
5. Priestley, J. H. and Scott, L. I. Branch Scars on Trees. Their 
Recording and Interpretation. The Naturalist, pp. 275-278, 1932. 
FIELD NOTES. 
Sparrow Hawk. — On 12th March, in the garden of Mrs. 
Darby, 25 Lond Lane, Dalton, Huddersfield, while birds 
were feeding on crumbs thrown for them, a Sparrow Hawk 
swooped down, and, seizing a Starling in its talons, flew off 
with it. 
This garden is at the side of a busy road, one-and-a- 
quarter miles from the centre of the town and in a fairly 
populous neighbourhood. — E. Gallwey. 
Little Owl. — A live specimen of the Little Owl was 
brought in to the Tolson Memorial Museum, Ravensknowle, 
Huddersfield, on the 10th inst. which had been caught in the 
back garden of Rawthorpe Hall, Rawthorpe Lane, Dalton, 
Huddersfield. — E. Gallwey. 
The Naturalist 
