6120 



Na tura l-History Collectors, 



dated two years subsequently to the introduction of gas, and its ravages have not yet 

 extended beyond the reach of the gas influence : that gas has an injurious effect on 

 elms is a self-evident fact, so probably have all gases evolved by combustion in facto- 

 ries, since we always see elms in manufacturing cities losing their leaves six or seven 

 weeks earlier than in the country : in this weakened state trees are particularly obnoxious 

 to the attacks of insects, and about London elm trees are generally infested with 

 the larvae of Scolytus destructor and Zeuzera iEsculi. I am well aware of the alleged 

 fact of the trees in the Hartz forest and elsewhere in France and Germany being 

 destroyed by Scolytus, still the coexistence of elm failure and gas-lights must remain 

 an indisputable fact, although at present a fact from which no general conclusions can 

 be safely drawn/' 



Mr. Westwood observed, with reference to the latter part of Mr. Newman's paper, 

 that the Scolytus was abundant in Christ Church Meadows, Oxford, far away from 

 gas-lights.'' 



Proceedings of Natural- History Collectors in Foreign Countries. 



Mr. A. R. Wallace.* — " Amboyiia, December 20, 1857. — My col- 

 lecting this year has been so peculiar and so diflferent from anything 

 I have yet done in the tropics that I must give you some little 

 account of it ; my locality was at the foot of the mountains about 

 thirty miles north of Macassar, the whole country between this range 

 and the sea is a dead level of paddy fields, flooded for half the year, 

 and of course absolutely barren of insects ; the mountains are of 

 limestone or basalt, the former rising from the plain in immense per- 

 pendicular walls quite inaccessible, except where a few streams break 

 through them ; the basalt hills are more rounded, and at the foot of 

 one of them is a forest of palms and jack fruit. I had a small bam- 

 boo house built ; when I arrived in August there had not been rain 

 for two months and it was fearfully hot and parched ; dead leaves 

 strewed the ground, and a beetle of any kind was sought for in vain. 

 After some time I found a rocky river-bed issuing from a cleft in the 

 mountains, and though dry it still contained a few pools and damp 

 hollows; these were the resort of numerous butterflies, — Papilio Eury- 

 philus, the new species near Sarpedon, P. Rhesus, P. Peranthus and 

 the rare P. Encelades, Bois., the beautiful Pieris Zaranda was rather 

 abundant, and several interesting Nymphalidae. Here, therefore, I 

 made daily excursions and procured good series of many of these 

 insects ; the paths in the forest adjoining this stream were pretty 

 abundant in Ornithoptera; of two species, O. Remus and the very rare 



* Communicated by Mr. S. Stevens. 



