INTRODUCTION. XXXV 



species are seldom seen, but can be freely secured by the use of 

 the sweeping-net in grasses and other short herbage ; this method 

 is particularly successful with the Capsidfe. The beating of the 

 leaves and twigs of trees by a stout stick over an open umbrella 

 is also a productive process. Other species, including many 

 Reduviids, may be netted on the wing, as they fly in the sunshine 

 like some Coleoptera. No inconsiderable number may be easily 

 picked from the leaves of trees ; and in the dry and cold season 

 a number hibernate, and may be found beneath stones, &c. Some 

 are attracted by the electric lights in the busy streets of towns, 

 and in the Transvaal I have taken many of the large aquatic 

 Belostomas in such situations. Among the Homoptera the large 

 Cicadas are to be detected by their shrill cries, and although 

 silence is observed when one approaches the trees from which 

 these sounds proceed, a careful search will usually result in the 

 discovery of the insect. Of the habits of some Rhynchota we 

 know practically nothing. Tingididse are generally found in the 

 sweeping-net, and some entomologists have never seen these 

 insects in situ. Some species are found blown out to sea at a 

 considerable distance from land, and the saloon deck of an ocean- 

 liner is often visited by many of these involuntary migrants. 

 Nezara viridula is a species frequently thus encountered, and is, 

 as recorded in these pages, of world-wide distribution. 



Classification. — Sharp estimates (1899) the total number of 

 Rhynchota described as about 18,000, two-thirds of the number 

 being Heteroptera. In Britain there are about 430 species of 

 Heteroptera and 600 of Homoptera. This is opposed to Scudder's 

 estimate that the Homopterous fauna of any given region of 

 considerable extent in the north temperate zone is to tlie 

 Heteropterous fauna as about one to three, or that about 25 per 

 cent, are Homopterous (Tertiary Ins. N. Amer. p. 2'SS). The 

 fact is that the smaller Homoptera have not been sufficiently 

 collected and described in most countries, and this explains the 

 divergence between the number of Heteroptera and Homoptera 

 in Britain and in other faunistic areas. A great disparity between 

 Homoptera and Heteroptera is exhibited in the enumeration of 

 fossil Rhynchota, but the difference in structural integument is 

 a sufficient explanation of the preservation of one ratiier than 

 the other. 



The Rhynchota are divided into two suborders, the Heteroptera 

 and Homoptera, by general consent, though Westwood in 

 his 'Modern Classiiication of Insects' (1840) — a work justly 

 considered as an entomological classic — kept both these divisions 

 as separate orders. They may be well separated by Sharp's 

 modification of the views of Schiudte. 



