64 FAUNA HAWAIIENSIS 



A number of interesting beetles breed only in this plant, and minute young of molluscs 

 and earthworms are generally abundant in the same, as well as the larvae of small 

 moths. Moreover nymphs of various sizes often frequent a single plant, and if hard 

 pressed for food the larger, no doubt, devour the smaller individuals. 



In consequence of these habits, some of these species of dragon-flies, although 

 their powers of flight are feeble, may often be seen in numbers in localities remote 

 from water, and where they would not naturally be looked for. 



These terrestrial nymphs are able to endure extreme drought. On one occasion 

 when out shooting, having no more convenient receptacle, I carried a number for 

 the greater part of the day in an envelope. In the evening, although very dry, they 

 were still quite lively. They were then placed in a tumbler of water, where they 

 remained on the bottom, not being able to crawl up the sides. Here they remained 

 for a day, apparently as happily as on dry land, when they were taken out and 

 preserved. 



M^Lachlan (Ann. Nat. Hist. (5) xii. (1883), p. 238) established a new genus 

 Megalagrion for the two species A. blackburni and A. oceanicuin, on the character 

 that the post-costal area was complicated by the division of its cellules. We have not 

 adopted that genus on account of the instability of the nervuration in this respect. 

 (Cf description of A. kauaiense, infra?) 



(i) Ag7'ion xanthomelas Selys. 



Agrion (.?) xanthomelas Selys, Synop. Agrionines, legion Agrion, p. 174. 

 M'=Lachlan, Ann. Nat. Hist. (5) xii. 1883, p. 232. 



(Plate V. figs. I, 4 & \a.) 



Hab. Probably occurs all over the Islands. Very common on Oahu, Maui 

 and Hawaii. Found both on the coast and in the mountains as high as 3000 ft. 



(2) Agrion pacificum M^Lachl. 



Agrion {?) pacificum M'^Lachl., Ann. Nat. Hist. (5) .xii. 1883, p. 234. 



(Plate V. figs. 6 & 6fl.) 



Hab. Not so abundant generally as A. xanthojfielas , but found on all the Islands. 



(3) Agrion hawaiiense M'^Lachl. 



Agrion (?) hawaiiense M^LachL, Ann. Nat. Hist. (5) xii. 1883, p, 232. 



Hab. " Oahu, at no great elevation above the sea." (Blackburn.) I have not 

 met with this species. 



