INTRODUCTION cxciii 



Sometimes after a short circular Hight they return to the tree from which they were 

 disturbed. They are very partial to Koa trees {^Acacia koa), but feed, so far as I have 

 observed, only upon the pods of these, extracting their juices. Whether they will 

 attack other parts in the absence of pods is very doubtful. They breed likewise very 

 freely on a very different tree, Dodotiaea viscosa, and both eggs and nymphs are 

 occasionally found on other plants. The two mentioned trees are, however, their 

 favourite food-plants. They have also been found breeding on imported Acacias. 

 Usually from Dodotiaea viscosa I have obtained the yellow form, with clear yellow 

 dorsal stripe, untinged with red, from Acacia koa the red form. Whether these varieties 

 depend entirely on the food-plant is, however, uncertain ; it is perhaps more likely due 

 to climate, the yellow variety being chiefly found in the driest localities. It is a 

 remarkable fact that the little Lycaenid butterfly, Lycaena blackburni, which holds a 

 position in the Hawaiian Lepidopterous fauna somewhat analogous to that of Oechalia 

 in the Heteropterous, feeds either in the pods of Acacia koa, or on the Dodonaea with 

 equal readiness and, so far as is known, on no other native trees. The small, globular 

 nymphs of the first stage are very conspicuous objects from the strong contrast of their 

 colours, the abdomen being for the most part bright red. 



LvGAEiD.\E. — If some doubt is attached to the endemicity of Coleotichus, this is 

 also the case with Itliamar hawaiiensis, which likewise is only known from the islands. 

 It abounds on the coasts of some of these, especially frequenting species of Sida, is 

 common on the lower edge of the forests in open shrubby places, at 1 500 to 3000 ft. 

 above the sea, and again in open places in still higher forest, and far above this to a 

 height of 9000 ft. At higher elevations it breeds on Cyathodes. Apparently it exhibits 

 no noteworthy variation in any of these stations. Nymphs in all stages, eggs, and 

 adults are found together on the plants named. The adults frequendy wander else- 

 where in their flight, and I have taken them in my garden in Honolulu. The hairy 

 nymphs undergo conspicuous changes in the course of their development. This is 

 probably the species that Blackburn supposed might be Dysdercus peruvianus. The 

 only other Lygaeid represented in the islands — Rhopabis hyalimis — is certainly an 

 introduction. Though common in Honolulu it was not obtained by Blackburn thirty 

 years ago. It is polyphagous, and its eggs and young are familiar objects on the plants 

 of Sonchus. The eggs are parasitized by two species of Proctotrupoids, Telenomus 

 rhopali and T. paractias. 



Myodochidae. — With this family we come to an extensive and important part of 

 the Heteropterous fauna. The genus Metr'arga with its two sub-genera is peculiar to 

 the islands, so far as is known, and, moreover, forms an endemic sub-family. The 

 number of species is at present uncertain, as those belonging to the typical sub-genus 

 are apparently very closely allied. Excepting in size there does not seem to be much 



F. H. I. bb 



