60 
OAK. 
moths fluttering among the leaves in the evenings. From sketch of 
size forwarded and description these were caterpillars of the regular 
Leaf-roller Moth, the Tortrix viridana, figured on p. 59. 
On June 23rd, by desire of Sir Harry Verney, of Claydon Park, 
Winslow, Bucks, a communication was forwarded to me by Mr. P. 
Sharp, the head gardener, mentioning that his fine old Oaks had been 
suffering from a.severe attack of what was considered to be the Oak leaf- 
roller caterpillar. The caterpillars had stripped the foliage completely 
off one tree, and had fallen in great numbers to the base of the tree, 
where they became a putrid mass, of which a lump was sent to me. 
The black decayed mass was formed of broken-up decayed cater¬ 
pillars, of which the head and broken pieces disengaged themselves 
and floated up on the surface when the lump was washed in a large 
bowl of water. At the time that the specimens were forwarded the 
caterpillars had gone through their change to chrysalis, but, from 
examination of the bright green contents of these chrysalids, likewise 
from the method of attack to the leafage, and also from the minute 
detailed description of the caterpillar which I had the opportunity of 
receiving personally while examining the trees at Claydon from Mr. 
Sharp, it was not open to doubt that the attack was of the Oak 
leaf-roller. 
The matter of the fall of the caterpillars from the tree is of 
considerable interest, as an example of the effects of sudden cold and 
wet in destroying these plant-vermin. 
On June 27th, Mr. Sharp forwarded a table of maximum and 
minimum temperature at Claydon during the time when he observed 
the workings of the caterpillars :— 
Max. 
Min. 
Rain. 
June 1 
65° 
42° 
— 
„ 2 
74° 
41° 
— 
„ 8 
75° 
45° 
— 
„ 4 
83° 
48° 
— 
„ 5 
77° 
56° 
0*15 in. 
ft 6 
63° 
53° 
0*15 „ 
„ 7 
68° 
50° 
0*05 „ 
„ 8 
60° 
54° 
0*59 „• 
„ 9 
64° 
46° 
— 
„ 10 
60° 
44° 
— 
„ u 
67 ° 
34P 
— 
tt 12 
75° 
45° 
— 
„ 13 
76° 
49° 
— 
„ 14 
77° 
49° 
— 
From this it will be observed that there was rainfall on four days 
after the max. temp, had risen to 83° in shade; but to continue 
in Mr. Sharp’s own words:—“ It was on the morning of the 11th (of 
