Insects. 



5889 



On the Entomologij of the Aru Islands. 

 By Alfred R. Wallace, Esq. 



Almost all that is known of the insects inhabiting New Guinea 

 and the adjacent islands is due to the French naturalists attached to 

 the numerous discovery ships which have visited that part of the 

 world. Many fine things have thus been made known to entomolo- 

 gists, although the total number of species collected is very small ; 

 and it may, perhaps, be considered as one of the least known and 

 most promising regions that remain, now that the most remote ^parts 

 of the earth are ransacked by enterprising collectors. These consi- 

 derations induced me to make a voyage to Aru in one of the native 

 prows which trade there annually, going with the west monsoon in 

 December, and returning with the east in June. I expected that these 

 islands lying so near New Guinea, and known to have some of their 

 most interesting animal productions (the birds of paradise for exam- 

 ple) identical, would yield me many New Guinea forms, and probably 

 some identical species, and my expectations in this respect have been 

 fully realized. The Entomology, the Ornithology, and certain pecu- 

 liarities in the physical geography of these islands, prove to me that 

 at no distant period (geologically) they formed a portion of the 

 southern peninsula of that great island, and have been separated from 

 it by a depression of the intervening portion (now a shallow sea), they 

 themselves remaining almost or quite undisturbed. I believe, there- 

 fore, that the insects of Aru and New Guinea are as closely related as 

 those of Great Britain and the Continent of Europe. 



It was with considerable anxiety that, on January 8th, 1857, I took 

 my first walk into the forest. The first insect I saw was not a very 

 encouraging one : it was the common Diadema Ange, found over the 

 whole Archipelago. A little further, however, and I was rewarded by 

 Idea d'Urvillei, a beautiful Hyades, the lovely Damis Coritus, Guer., 

 and that superb insect Cocytia d'Urvillei. Two or three pretty Lyce- 

 nidae of genera unknown in the western parts of the Archipelago, 

 Tricondyla aptera, and two species of the longicorn genus Tmesi- 

 sternus, with several smaller insects, composed my first day's sport; 

 and a very satisfactory one it was, for it assured me there was work to 

 be done, and that I was really in the midst of a New Guinea Fauna. 



I collected steadily for two months in this jungle, situated in the 

 small island of Wamma, at one end of which is the Bugis settlement 

 of Dobbo, where I resided. I got a great many nice things, but the 

 XVI. F 



