Packard.] INSECTS OF THE PLANT HOUSE. 
113 
Orange). The dark part is the insect, the pale portion the 
cottony or woolly down enveloping the eggs and young 
larvae. The female is flat and scale-like, while the male is 
two-winged. All these scale insects are closely allied to the 
wax producing Coccus. 
Professor Silliman informs us, in the “American Natural¬ 
ist,” that it may be “ interesting to non-chemical readers to 
know that this insect wax is a definite compound somewhat 
resembling spermaceti in appearance, but not in compo¬ 
sition, being a cerotic ether known as cerotate of ceryl, of 
the formula C 59 H 1118 O 2 . It is crystalline, and of a dazzling 
whiteness like spermaceti, but more brittle and of a more fi¬ 
brous texture. It does not completely saponify by boiling in 
potash water, but is completely decomposed when melted with 
potash, yielding cerotate of potassium and hydrate of ceryl. 
It is consumed in China for candles and also as a medicine. 
It melts at about 118° F.” Prof. Silliman quotes from a 
recent book by C. C. Cooper (Travels of a Pioneer of Com¬ 
merce in Pig Tail and Petticoats, etc., London, 1871) the 
following interesting account of the cultivation of this wax 
insect. “ On the third day we entered the white wax coun¬ 
try, so named from its producing the famous white wax of 
Szchuan, which has been erroneously called vegetable wax. 
This district was less undulating than that of the tea gardens, 
and presented to the eye a view of extensive plains sur¬ 
rounded by low hills. The plains were all under wax and 
rice cultivation, the wax trees being planted round the 
embankments of the small paddy fields, which were at most 
thirty yards square. The country thus presented to the pass¬ 
ing traveller the appearance of extensive groves of tree 
stumps, each as thick as a man’s thigh and, all uniformly cut 
down to a height of about eight feet, without a single branch. 
The cultivation of wax is a source of great wealth to the 
province o£ Szchuan, and ranks in importance second only 
to that of silk. Its production is not attended with much 
8 17 
