v1 INTRODUCTION. 
The Aradide, so far as at present known, have the same number of representatives 
as the Tingitidee within our limits. They are nearly all found under the bark of 
fallen or decaying trees, often in gloomy places in the forest. Some of them have 
the upper surface more or less coated with a hard pallid incrustation, which is moulded 
into peculiarly-shaped prominences on the head, pronotum, and scutellum, the use of 
which it is difficult to understand. Seventy-eight species are enumerated, with forty 
new, and five new genera. 
The Hebride is a family of very limited extent, the species all being of subaquatic 
habits. Eleven species are here recorded, seven of them being treated as new. 
The Hydrometride are spread over all parts of the world, many small islands 
having one or more representatives, and some of the genera are very widely distributed. 
They live upon the surface of fresh, brackish, or salt water. Within our limits, the 
subfamily Veliine, so far as can be judged from the collections obtained by our 
Editors, is much more numerous in species than the Gerrine; but as the latter are 
usually very difficult to secure, this may not really be the case. For the whole 
family (exclusive of the pelagic Halobatine, which are not dealt with here) forty 
species are enumerated, including twenty-nine previously undescribed, and two new 
genera. 
The Henicocephalide is a widely distributed family including but few species. The 
single American genus is known under various different names. These insects have 
the head very peculiarly formed, the anterior legs raptorial, and the elytra uniformly 
membranous, so that they can be readily used for flight. Of the six species enumerated, 
all but one are treated as new. 
The Reduviide is one of the most extensive families of Heteroptera. They are 
chiefly confined to the tropics, becoming much less numerous in temperate regions. 
Lethierry and Severin (1896) enumerate 1877 (counted up in their summary as 1835) 
species for the whole world, exclusive of the Nabide. Amongst the known Tropical- 
American genera there are a considerable number that do not extend so far north 
as the Isthmus of Panama, while, on the other hand, Apiomerus, Zelus, &c. are 
particularly well represented. These insects are all blood-suckers, Conorrhinus being 
said to attack man, and many of them have the power of exuding a viscous liquid 
for the purpose of retaining a secure hold of the species upon which they prey. The 
