LOW TEMPERATURES VS. SCALE INSECTS. 73 
Results obtained by exposing orange scale insects, §¢c.—Continued, 
T|* | | 
iE | Time from | 
. Minimum aximum | a exposure | 
M No. of tempera- tempera- | Time of | Result to | aeesut to tinal Remarks. 
experiment. ate ture. | @XPosure. larve. | to eggs. collapse of 
| iid larve. , | 
— —== ya - | 
| 
Hours. | Days. 
1 ett eee 29 29 1 Dead :--| Hatch --| IB 
eae aes 29 32 14 Poms asie donee 5 | 
Ay Bees ae 29 34 2 _.do PPP Xi ines 6 | 
Pea tet cre 30 32 16 SoC (epee ce Opec: 
Wiese case. - es 30 32 10 Sedo aaeale- G0tscs: 10 
EG este. 52 5 32 32 12 dome a= |= Gdons=-- 10 
Wit ouck stas, 32 32 5 ee COl Senay bac OOr-cae. 5 
Bias eecon: 32 34 14 [edoteeso.| en G0 6 
LCE Sees oe 34 34 iy: ido} Sil dO ec. 3 
PA Vga el See 34 34 $ POON sence) donc 3 
PAT RS ee 34 34 2 ee MOG? 24h-4- doys.5 es | 6 
22. 36 36 2 eiQO meer ease =: 8 
DECEMBER 26, 1885. 
During my recent absence from home there was a short period of cold 
weather, which on my return I found had produced naturally nearly all 
of the conditions that in my experiments were produced artificially. 
Although I was only 10 miles directly south of here, at the place where 
I was the effects were very slight, and near by there were no traces of 
frost, tomatoes and bell-peppers out of doors being unhurt. 
Had I known in time the extent of the damage elsewhere I could have 
made some valuable observations. 
The thermometer is reported at various figures, ranging from 21° F. 
to 30° F. The effects show as wide a difference. 
In the same neighborhood I find young orange trees killed to the col- 
lar at the ground, and orange and lemon trees that are unhurt, and 
these are sometimes within a few yards of each other. 
Six days after the frost, examination showed that the defoliated 
branches infested by insects were dead, whilst others not so exposed 
were living, and that where the small twigs were not killed there were 
some living eggs. 
I also find the same appearances as in the experiments, eggs 
living in the same scale. 
The stated probable effects of the 
dead and 
initial heat of the tree, &c., are re- 
alized and very distinctly marked. I inclose a twig showing this. The 
outer portion is dead, and the eggs are alsodead. The basal portion cut 
from near the body of the tree is living, and there are also there at this 
writing some eggs that are clear and pink. 
This cold term was calm, the greattst cold of short duration, not more 
than an hour. The conditiens were as nearly a reproduction of those of 
the experiments, probably, as ever occurs naturally, and the results are 
so similar as to give greater value to the information artificially ob- 
tained. 
Respectfully, 
JOS. VOYLE. 
Prof. C. V. RiLtEy, U. S. Entomologist. 
