Part 23

A paper by Mr R Chambers on the subject adduces the additional testimony of facts observed by good naturalists, as Dickson and Curtis the eminent botanists, and Stothard the painter and entomologist, by his own father Mr A. Chambers, and by Joseph Simpson, a fisherman living near Boston, all of which strongly corroborate the probability that some, at least, of the ignes fatui are produced by luminous insects. Mr Main narrates the case of a farmer who stated that he had pursued a Will-o'-the-wisp, and coming up with it had knocked it down, when it proved to be an insect "exactly like a Maggy-long-legs"--that is, the common Crane-fly (Tipula oleracea), the very insect with which Mr Sheppard had compared the motions of the luminous flame observed by him. Mr Spence argues that while gaseous emanations may be a cause of stationary ignes fatui, the same cause will not explain those which flit along from place to place; and that these are probably luminous insects, however rarely they may have come under the notice of entomologists. "A very strong argument for the possibility of some flying insects being occasionally luminous (in England) is afforded by the facts ... of luminous caterpillars having been within these few years observed for the first time since entomology has been attended to, and that by observers every way competent. If caterpillars so very common as those of Mamestra oleracea may sometimes, though so rarely, be luminous, and if, as Dr Boisduval suggests, and is very probable, this appearance was caused by disease, it is obvious that flying insects may be also occasionally (though seldom) luminous from disease--a supposition which will at once explain the rarity of the occurrence, and the circumstance that insects of such different genera, and even orders, are said to have exhibited this phenomenon."

These highly curious facts should make observers cautious in strongly denying statements made by others of phenomena, when they themselves have not been so fortunate as to witness them, even though they may think their opportunities to have been as favourable as those of the soi-disant observer.

But we have not yet dismissed Madame Merian. If acquitted of falsehood here, she stands arraigned on a second charge of similar character.

In most tropical countries there are found hideous hairy spiders of monstrous size and most repulsive appearance; short-legged, sombre-hued, ferocious marauders of the night, that by day lurk in obscure retreats under stones, or in burrows in the earth.

Guiana produces a formidable species of this sort (Mygale avicularia), which measures three inches in length, and whose feet--though the genus is, as I have said, comparatively short-limbed--cover an area some eight or ten inches in diameter. Madame Merian has exquisitely figured the tragical end of a tiny humming-bird, surprised by one of these monsters on her eggs; the petite bird overthrown under the fangs of the sprawling spider, one of whose feet is in the nest. It was on the authority of this lady that Linnæus gave the name of avicularia to the species. Later naturalists have scouted the whole story. Mr MacLeay, who resided in Cuba, says that there are indeed there huge spiders, allied to our garden spider, which make a geometric net, strong enough to embarrass small birds; but that these do not attempt to catch such prey, and never molest birds at all. On the other hand, he avers that the Cuban Mygale, an allied species to that of Guiana, makes no web, and has no power of injuring birds. He put this to the test of experiment; for having maimed a humming-bird, he thrust it into the Mygale's hole, which, instead of seizing the victim, retreated as in fear out of his den. This Mr MacLeay supposes to be conclusive; but a moment's reflection will shew how equivocal is the evidence. The spider may not have been hungry; or he may have been taken aback by the sudden intrusion; or he might not choose to take prey that he had not stolen upon and slaughtered suo more; or he may have muttered in the Arachnidan language,--

"Timeo Danaos, et dona ferentes."

Because a wolf will cower down in the corner of his lair (even a tiger has been known to do so)--when a man suddenly enters his presence, and will manifest the most abject fear, would it be philosophical to ridicule the tales told of wolves pursuing and devouring men by night?

M. Langsdorff asked the people of Brazil if the Caranquexeira, or the great Mygale of that country, fed upon humming-birds, when they answered him, with bursts of laughter, that it only gratified its maw with large flies, ants, bees, wasps, beetles, &c.; an answer which the traveller verified by his own personal experience. If M. Langsdorff means, which of course he does, that he learned by personal observation that the spider ordinarily feeds on insects, that fact is indubitable, and never has been doubted; but if he means that he had experience that it eats only such prey, which is the question at issue, it is plain that this experience proves no more than that he never witnessed such a fact.

Percival, in his account of Ceylon, observes:--"There is an immense spider here, with legs not less than four inches long, and having the body covered with thick black hair." This was doubtless the Mygale of the island. "The webs which it makes are strong enough to entangle and hold even small birds, which form its usual prey." Alluding to this statement, Sir Emerson Tennent says:--

"As to the stories told of the Mygale catching and killing birds, I am satisfied, both from inquiry and observation, that, at least in Ceylon, they are destitute of truth, and that (unless in the possible case of acute suffering from hunger) this creature shuns all description of food except soft insects and annelides." And yet he immediately adds:--"A lady at Marandan, near Colombo, told me that she had, on one occasion, seen a little house-lizard (gecko) seized and devoured by one of these ugly spiders." Does he not, then, credit his informant? Or are lizards included in the category of "soft insects and annelides?"

Against this incredulity, resting on no better than negative evidence, one might adduce collateral proof from analogy. There are spiders which feed on vertebrate animals, and there are spiders whose webs catch birds. The large and beautiful Nephila claripes of tropical America weaves strong threads of yellow silk in the paths of the woods, converging to a web quite strong enough to arrest a bird of weak flight. It must have been a species allied to this, but certainly, I think, not the same, of which Dr Walsh speaks in his "Travels in Brazil." "Among the insects is an enormous spider, which I did not observe elsewhere. In passing through an opening between some trees, I felt my head entangled in some obstructions, and on withdrawing it, my straw hat remained behind. When I looked up I saw it suspended in the air, entangled in the meshes of an immense cobweb, which was drawn like a veil of thick gauze across the opening, and was expanded from branch to branch of the opposite trees as large as a sheet ten or twelve feet in diameter. The whole of this space was covered with spiders of the same species but different sizes; some of them, when their legs were expanded, forming a circle of six or seven inches in circumference. They were particularly distinguished by bright spots. The cords composing the web were of a glossy yellow, like the fibres of silkworms, and equally strong."

There is a creature found in the tropical parts of both hemispheres, called Solpuga, which though not exactly a spider, is yet so closely allied to that family as to be in some measure responsible for its misdoings. It is about as large as the Mygale, and, with sufficient general resemblance to it to warrant its being popularly considered a spider, it has much the same habits and appetites. Captain Hutton, in a most interesting memoir, describes the details of an Indian species under the name of Galeodes vorax. Among many other details, he says--"This species is extremely voracious, feeding at night upon beetles, flies, and even large lizards; and sometimes gorging itself to such a degree as to render it almost unable to move. A lizard, three inches long, exclusive of tail, was entirely devoured; the spider sprung at it, and made a seizure immediately behind the shoulder, never quitting its hold until the whole was consumed. The poor lizard struggled violently at first, rolling over and over in its agony, but the spider kept firm hold, and gradually sawed away with its double jaws into the very entrails of the victim. The only parts uneaten were the jaws and part of the skin, although the lizard was at least five inches long from nose to extremity of tail. After this meal, the spider remained gorged and motionless for about a fortnight, being much swollen and distended.

"A young sparrow, about half grown, was placed under a bell-glass with a Galeodes; the moment the luckless bird moved, the spider seized him by the thigh, which he speedily sawed off, in spite of the sparrow's fluttering; and then as the poor bird continued to struggle in pain, the savage seized him by the throat, and soon put an end to his sufferings by cutting off the head. It did not, however, devour the bird, nor any part of it, but seemed satisfied with having killed it.

"On another occasion, I gave it a large garden-lizard, which was instantly seized by the middle of the body; the lizard, finding that it could not shake off its adversary, turned its head, and bit the Galeodes on the leg, which obliged it immediately to quit its hold and retreat.

"On another occasion my friend, Dr Baddeley, confined one of these spiders in a wall-shade with two young musk rats (Sorex Indicus), both of which were killed by it."

In an expedition to the Kurruckpoor Hills, south of Monghyr, Captain Sherwill found upon the summit of Maruk, a table-topped hill of 1100 feet elevation, several of the gigantic webs of the Epeira spider, some of which measured (including the guy-ropes) from ten to twelve feet in diameter, the reticulated portion being about five feet, in the centre of which the spider, of a formidable size and very active, sits waiting for prey. "The webs," he says, "from their great strength, offered a sensible resistance when forcing our way through them. In the web of one of the spiders we found a bird entangled, and the young spiders, about eight in number, feeding upon the carcase. The bird was, with the exception of its legs and beak, entirely enveloped in the web, and was much decomposed; the entwined web had completely pinioned the wings of the bird, so as to render its escape impossible. The bird was about the size of a field-lark, and was near the centre of the web; the old spider was about a foot above the bird: we secured, measured, and bottled him. Its dimensions were six inches across the legs, and it was armed with a formidable pair of mandibles."

It is clear, then, that there is nothing absurd or contrary to probability in the statement that spiders attack, overcome, and devour birds. But Madame Merian is here again favoured with direct witnesses to sustain her good faith. M. Moreau de Jonnès expressly mentions, on his own authority, that the South American Mygale climbs the branches of trees to devour the young of humming-birds. But the most satisfactory statement is made by Mr H. W. Bates, who has recently returned from the interior of Brazil after many years spent in studying the entomology of that vast region. No one will deny his competency as a witness. "Now I will relate to you," he says, "what I saw in the month of June 1849, in the neighbourhood of Cameta. I was attracted by a curious movement of the large gray-brown Mygale on the trunk of a vast tree: it was close beneath a deep crevice or chink in the tree, across which this species weaves a dense web, open for its exit and entrance at one end. In the present instance the lower part of the web was broken, and two pretty small finches were entangled in its folds; the finch was about the size of the common siskin of Europe, and I judged the two to be male and female; one of them was quite dead, but secured in the broken web; the other was under the body of the spider, not quite dead, and was covered in parts with the filthy liquor or saliva exuded by the monster. I was on my return from a day's excursion by land at the time, with my boxes full of valuable and delicate insects, and six miles from my house, and therefore could not have brought the specimens home, even if I had wished, which I did not, as the spider was a very common species, easily to be procured nearer home. The species I cannot name; I sent several fine specimens, stuffed, to London, in 1851; it is wholly of a gray-brown colour, and clothed with coarse pile. Doubtless you will immediately know the exact species to which I refer.

"If the Mygales did not prey upon vertebrated animals, I do not see how they could find sufficient subsistence.

"On the extensive sandy campos of Santarem, so bare in vegetation, there are hundreds of the broad slanting burrows of the large stout species, (that fine one, dark brown with paler lines down the legs, of which I sent specimens in 1851.) The campos, I know, from close research, to be almost destitute of insects, but at the same time to swarm with small lizards, and some curious ground finches of the Emberiza group (one of which has a song wonderfully resembling our yellow bunting of England), besides which, vast numbers of the Caprimulgidæ and ground doves lay their eggs on the bare ground.

"I believe this species of Mygale feeds on these animals and their eggs at night. Just at the close of day, when I have been hurrying home, not liking to be benighted on the pathless waste, I have surprised these monsters, who retreated within the mouths of their burrows on my approach."

Brit. Rept., 51.

Penny Cyclop., xxvi. 348.

Loudon's Mag. Nat. Hist. for 1837, p. 441.

Zool., 2305.

Ibid., 2355.

Zool., 7278.

Captivity among the Indians.

Zool., 2269.