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Record number: WCP4812

Alfred Russel Wallace
[not recorded]

Record created:
26 October 2012 by Beccaloni, George


No summary available at this time.

Record contains:

  • manuscript (1)

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Manuscript entitled "Stray notes on tropical insects", containing notes on the biology and behaviour of beetle species and a spider as observed by ARW in S.E. Asia.

Handwritten by author in English.

Held by:
Natural History Museum
Finding number:
NHM WP18/45
Copyright owner:
ŠA. R. Wallace Literary Estate

Physical description

Transcription information




Stray notes on Tropical Insects.

Buprestida. No beetles take wing so rapidly as these. They require the utmost activity & a strong handled net to catch them. The reason seems to be that their wings are not folded transversely, being exactly of the same length as the elytra, so that there is not that momentary delay required to unfold the wings which takes place with all other coleoptera I am acquainted with, & gives a chance to capture them just as they are starting. They love the hottest sunshine, settling on fallen timber so abruptly that a distinct knock can be heard; & on the slightest alarm they are off with as much ease & rapidity as a fly or a cicada. Belionota is a very active genus Chrysochroa less so Chrysoderina very sluggish. As they want an English name I call them "Sun beetles", for I never take them on a cloudy day.

Brenthidae. I have a species from Aru two inches long and about a line wide, an extraordinary looking creature as it walks slowly about on a piece of timber, its back high up & its long snout bent down as if looking after something which it probably is. One day I saw two of these creatures fighting: -- each had a fore leg across the neck of the other, their rostrums bent & crossed; -- they appeared in a dreadful passion; but like many passionate people looked supremely ridiculous. Another time a large & a small male had a fight for a female who stood close by with her rostrum buried up to its base in a hole she was boring for her eggs. These pushed at each other with their snouts, [[2]] and clawed & thumped most furiously but were evidently quite unable to hurt each other. However the little one soon got frightened & ran away. The form of the rostrum is a sexual character, the females have it finely pointed, the males dilated at the end.

Instinct at fault. The little cylindrical wood boring beetles (Platypus sp.) attacked a newly fallen tree, but most rashly for when the bark was pierced a milky sap exuded which hardened the exposure to the air, glueing the little insects with the holes they had bored. Dozens were to be seen dead stuck fast in the graves they had themselves dug, their hind legs & the apex of the elytra only protruding. Yet day after day fresh borers were at work only to perish like their predecessors.

Query. Do not we often impute instinct where it does not exist, simply because in the cases where it fails the individuals perish. The fops who admired the faultless tie of Beau Brummel[sic]1’s cravat knew nothing of the mornings’ two dozen [2 words crossed out illeg.] failures, 'ere that brilliant success had been achieved.

Crabs & Spiders. The Hermit crabs are very abundant in the forests of Aru which they have thickly strewed with dead sea shells. They not only crawl along the paths but climb up trees & shrubs and it is at first very puzzling to see Trochi & Murices in such a situation till you observe what has brought them there. But what is more strange you often see a large spider carrying one of these shells in his arms and running away with it if alarmed, & on more close examination it will be seen that [[3]] he has made the lodger his prey and is sucking out the life blood of the poor hermit. That spiders kill and eat crabs as big as themselves is a strange and perhaps a new fact.


The beetles of this genus are almost exclusively arboreal, though I have found them occasionally on the ground and also on the stems of a large grass. Generally however they inhabit the trunks of large forest trees, about which they run pretty actively. On being approached they run spirally round the trunk so as to keep continually on the opposite side from their pursuer, just as many creepers & woodpeckers do. They never fall to the ground & can not be caught with the net by pushing or striking, however quickly the operation may be performed. The only way of capturing them is with the hand, by approaching as near as you can unperceived, & then suddenly clapping the hand over them. They have little or no odour & emit no disagreeable fluid neither is their bite at all painful, though on first acquaintance they do look rather formidable. Therefore resemble ants for Protection.2 They are very clever at disappearing altogether & I have often wondered where they could have got when on running round a small smooth tree up which they one was spirally mounting I have unable to perceive any trace of him. They are always found in the deep virgin forest.


Therates. This genus is equally a forest insect with the last & frequents generally gloomy paths, ravines & the rocky margins of fresh streams. The species are all very active on the wing, scarcely ever running except for very short distances. They are found on low foliage, on rocks & on fallen tree trunks. They continually take short flights of a few [word crossed out illeg.] yards at a time. Many of the species emit a fine odour perhaps superior to that of the Callichromae, to which it is very similar. The large T. labiata of the Moluccas & N[ew]. Guinea is particularly fragrant. They are often very local being found only in one or two spots in an extensive forest. They rarely or never settle on the level ground, though often on rocks.


These elegant insects are found exclusively on foliage. I never remember to have seen on settle on the ground or on rocks trunks or branches. They are very active and take rather longer flights than the Therates. They also frequent more open, light, & sunny places. They have no peculiar odour. They seem to prefer shrubby to herbaceous plants, & keep habitually rather higher above the ground than the Therates.


1. George Bryan "Beau" Brummell (1778 - 1840), iconic figure in Regency England and arbiter of men’s fashion.

2. This sentence is written vertically upwards in the left margin.

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