c FAUNA HAWAIIENSIS 



Sierola, that I bred from dead wood attacked by these and other Coleoptera. The 

 species of Sierola are apparently somewhat variable and not always easily distinguished, 

 and I rather suspect that they were more numerously represented in my collections, 

 than is shown by Ashmead's discrimination of them. 



These two genera embrace all the truly endemic Bethylidae, but in addition to 

 these there have been described from the islands two semi-domestic species of 

 Holepyris, as well as a species of Sierolomorpha (probably better referred to the 

 Cosilidae). Of little importance, and at present undetermined, are a species of 

 Ateleopteriis parasitic on some of the insects (probably Coleopterous) that destroy 

 stored seeds and grain, and a minute Cephalonomia that attacks the ubiquitous Scolytid, 

 Hypothene^nus erzidihis. 



Dryinidae. — This family is represented by a single species of the Australian genus 

 Echtlirodelphax, and one, or perhaps two, species of the widely spread genus Pseudo- 

 gonatopus. The former is likely to be found elsewhere, being indeed extremely closely 

 allied to an already known Australian species. It attacks Delphacid leaf-hoppers 

 of various kinds, but apparently only on the lowlands or at low elevations, not being 

 a true forest insect. The larval sac is placed beneath the lobe of wing or tegmen and 

 a hopper frequently carries two of these parasites. In some cane-fields this parasite 

 has reached extraordinary numbers at certain seasons, attacking the swarms of nymphs 

 of the imported leaf-hopper of the sugar-cane. The larvae of Echtkrodelphax like 

 those of many other Dryinidae, are themselves attacked by chalcidoid parasites, which 

 are almost certainly of foreign origin. 



The Hawaiian representative of Pseudogonatopus is an anomalous representative of 

 the genus and shows the most extraordinary variability in colour, some examples being 

 nearly black, while others are quite pallid and in parts almost whitish. They vary both 

 individually in one locality, and also very greatly, when taken in different localities- 

 There are all sorts of intermediate conditions between the extremes. Ashmead 

 recognized two species, but was doubtful as to their distinctness. Labco hawaiiensis is 

 the male of Pseudogonatopus perkinsi, the sexes having been bred several times. This 

 Dryinid is found in the forests of all the islands, in very diverse localities, and attacking 

 species of several genera of the endemic Asiracid leaf-hoppers. It is subject to the 

 attacks of chalcid parasites of the Mirine group of the Encyrtidae, which attack its 

 larvae, while still adherent to the leaf-hopper. Possibly owing to these parasites, the 

 adults of Pseudogonatopus are less common than would be expected from the number of 

 parasitized hoppers that are frequently seen. We have bred this insect from eggs laid 

 parthenogenetically, although males appear to be constantly produced by the species. 



PoNERiDAE. — The exponents of the genus Ponera are no doubt introductions, 

 ■excepting the forest-haunting P. perkinsi, which is rarely found on the lowlands. It 



