2 
TRANS. S. D. Society NATURAL History 
feet. “The Willows,” two miles farther east, gives good valley con- 
ditions. 
Hurlburd Ranch, near Descanso, altitude about 4000 feet, with 
conditions not very different from those found at Alpine. 
“Twin Pines,” on the road from Descanso to Julien and at an 
altitude of about 5000 feet. This was the highest point accessible 
by road in the Cuyamaca Mountains, and the vegetation was quite 
different from that found at lower levels; pine, broad-leaved oak, 
alder and cedar trees and many other more northern species being 
found here, and the insect collecting was distinctive and good. 
Pine Hills, near Julien, altitude 4200 feet, was an excellent col- 
lecting ground with some of the mountain vegetation found at the 
“Twin Pines.” 
In San Diego County the collecting season for Hemiptera ex- 
tends over the entire year, but most of the species have their regu- 
lar season depending perhaps more on the rains than on the alti- 
tude of the sun. The greater number appear soon after the rains 
and are “in season” from March to July, while certain species and 
straggling examples of others may be found until well into October. 
In the higher altitudes from Alpine into the Cuyamaca Mountains 
the season is later. Introduced species on alfalfa and other crops 
are found throughout the year. 
The lower lands near the coast are usually frostless or nearly 
so, but from about 1500 feet up there may be a few frosts severe 
enough to injure tomato plants if unprotected and most every win- 
ter there is a little snow on the Cuyamaca Mountains which may re- 
main on the ground for a day or two. In the severe freeze of Janu- 
ary, 1918, the temperature reached 16 degrees in San Diego city 
and went as low as 6 degrees in some of the neighboring canyons, 
but the exceptional severity of this freeze is proven by the fact that 
rubber trees more than fifty years old were killed to the ground; 
but even these conditions were local and tender vegetation not far 
distant would sometimes escape almost untouched. 
One from the east is surprised to find that with such a climate 
there is both hybernation and estivation among the insects. The 
principal controlling factor here is the moisture conditions. The 
rains, amounting to from ten to sixteen inches according to altitude, 
come during the winter months, from November to April, and this 
rainy season is the time of green fields and of flowers which appear 
in marvellous profusion and beauty. The young of many plant- 
feeding Hemiptera appear during February and March, but certain 
species occur much later. 
On the eastern slope of the Cuyamaca Mountains the fauna 
partakes more of the desert type, but the little collecting I have 
done at Buckman’s Springs and in Pine Valley was insufficient to 
indicate the character of that fauna. In addition to the species 
enumerated in this paper I have taken quite a number that I have 
been unable to determine with the material and time at my dis- 
posal. 
I wish here to acknowledge my indebtedness to Mr. W. S. 
