a List of the Butterflies of Hong-Kong, 435 
largest of a group of sraall rocky islands off tlie mouth 
of the Si-Kiang, the great river on which Canton stands. 
It is about 10 i miles in extreme length, with a width 
varying from two to five miles, and embraces an area of 
a little less than thirty square miles. Generally it may 
be described as a mass of rugged hills of moderate 
elevation, separated from each other by deep ravines, and 
sloping steeply down to a much indented and usually 
rocky coast-line. Granite, and diorite or greenstone, 
form the basement rocks of the island, overlaid by more 
recent but still very ancient beds of quartz -porphyry and 
other old volcanic rocks, the whole greatly worn down by 
sub-aerial denudation. The granite is of fairly good 
quality as a building-stone, but where it is exposed, it is 
weathered, sometimes to the depth of many feet, by the 
action of tropical rain and heat, into a soft friable mass, 
which, while at first sight it appears to retain all the 
structure and properties of the original rock, may yet be 
readily dug into with a spade. Such beds of decayed 
granite are to be seen to great advantage on the west 
side of the Wong-nei-chong, or " Happy Yalley ; and 
they often contain huge masses of the parent rock, of 
harder texture than the rest, which have resisted the 
weathering action, and look deceptively like errafcic 
boulders. Generally speaking, the soil is of a harsh and 
unkindly nature, and, except in a few places, it is of but 
little use searching for ground-frequenting Coleoptera; 
very few insects being found under stones in the cooler 
months, with the exception of huge wingless cockroaches 
of three or four species. 
Although the island of Hong-Kong has now a popula- 
tion of upwards of 200,000 inhabitants, it is nearly all 
concentrated in the city of Victoria, which extends for 
some three miles along the north shore, and about half- 
a-mile up the slope of the hills, on the summits of which 
are many fine villa residences and hotels. A few Chinese 
villages are scattered round the coast, but with these 
exceptions, the island is almost entirely wild and un- 
cultivated. Some rice used to be grown in the W ong- 
nei-chong valley, but its cultivation was prohibited as 
unhealthy, and there are now only a few market-gardens 
near the city, which derives most of its supplies of 
fruit and vegetables from Canton. The hills, which 
attain an elevation of 1,500 to 1,700 feet (Victoria Peak, 
