INTRODUCTION cxcix 



sailing- round the coast of Hawaii near Kawaihae, but never had an opportunity of 

 collecting specimens. 



Microvelia vagans is an abundant species and widely distributed in the islands, 

 from the coast to high mountain elevations. It frequents both stagnant pools and 

 running water, often in great numbers, and after heavy rains is sometimes seen even on 

 the temporary puddles in the roads round Honolulu. It flies by night and occasionally 

 is attracted by lights. Possibly it will be found elsewhere and is a natural immigrant, 

 though it may have been of early introduction in the water supply of sailing vessels. 

 It exhibits considerable variability in colour, but this has not been specially investigated 

 in reference to different localities. 



Reduviidae. — This family is represented by endemic species of the Ploiiariianae 

 and three imported species of other groups, none of the latter being found in 

 Mr Blackburn's collection. One, indeed, Ze/iis renardii, was introduced about 1897, 

 when I observed one or two specimens, including a female by the side of its egg-mass, 

 at Honolulu in the Government Nursery, where plants were introduced and raised 

 by the Board of Agriculture for general distribution. By 1900 it had become fairly 

 common in Honolulu, and three years later extremely so, and had spread to all the 

 other islands. It preys on very different kinds of insects, and the adults will destroy 

 many kinds of beetles, such as Dermestids, Coccinellids and Tenebrionids, and even the 

 hard Hymenopterous genus Chalcis. The young feed on softer creatures, especially 

 Aphis, young leaf-hoppers, etc., which are also attacked by the mature bugs. Although 

 destroying an occasional lady-bird, when well-grown, yet the main food of Zeliis, as an 

 adult, consists of injurious insects or at least of such as are not beneficial, while the 

 young prey almost entirely on injurious species. Consequently, on the whole, Zelus 

 does far more good than harm. 



Triatoma rubrofasciata has several times been found in houses or outhouses in- 

 fested with cockroaches or bed-bugs. Alloeocrantim bianmclipes has only occurred once. 

 The endemic genus N^esidiolestes is said to be allied to Luteva and Ploiariodes, the 

 other two Ploiariine genera represented. The species are terrestrial and have been 

 found in company with the flightless Reduviohis. Luteva and Ploiariodes prey on 

 Psocidae; a species of the former is occasionally found in houses in Honolulu. The 

 number of species of the latter is at present uncertain ; they are usually found on dead 

 branches of trees, to which the dry leaves are still attached, and on dead fern fronds, 

 whereon their prey is numerous. 



Anthocoridae. — This family is represented by a small number of species scattered 

 in half-a-dozen genera and although these species are all, at present, known only from 

 the islands, it is uncertain whether several of them are not really introductions, their 

 small size, and unattractive appearance rendering them liable to be overlooked in 



