Eye Spy Part 11

On a certain afternoon last August, having just completed a particularly laborious work upon which I had long been engaged, and with my mind naturally inclined towards relaxation in my plans for the morrow's labors, my eye instinctively sought a certain note-book upon my table. It was a note-book containing memoranda on a wide variety of Nature topics, but presented in a particular place a choice, selected list of topics under the t.i.tle of "Young People." A large number of these memoranda were crossed off with a pencil line, which told me that these particular topics had already served their purpose, were sufficiently elaborated in the columns of the "Young People," and were now safely preserved between the covers of my book "Sharp Eyes."

But what an array of items were still left from the winnowing, which had after all culled only a few of the best! Indeed, it was hard to decide which should be selected as the subject for the morrow. Let's see; shall it be those travelling underground buds of the Clintonia, with all their leaves and flowers ready for next spring? No, I must wait a little for these a month later and they will be more mature, and I must make my drawing from nature. Then there is that queer blue oil beetle, with his queerer history; that slender-waisted wasp that digs its deep hole in the dirt, and those round holes in the path, with their mysterious hocus-pocus.

Yes, it shall be these, the magic holes that disappear as you cautiously look at them, or suddenly start into view as you approach--deep holes, the diameter of a slate-pencil, with apparently nothing in them, but which in reality have a good deal of mischief at the bottom of them or at the top of them, as it happens. "Ant holes,"

most people call them. Many an ant, doubtless, goes into them, but not because he wants to. "Yes," I thought, "my next chapter shall be devoted to these queer holes and their shy tenants, which so few people ever see or even dream of."

Having thus decided, I closed my note-book, but the experience of the next few minutes quite reversed my plans, and led to the completion of an entirely different article, or the pictures for it at least, on the same afternoon, without awaiting the morrow.

I had barely closed the note-book when, chancing to glance out of my studio window, I observed a well-known neighbor, a thrifty, retired granger and carpenter, approaching across lots. His house stood out against the sky at the crest of the slope, about a furlong distant, above my studio, and he had perhaps reached half-way to my window before I had observed him. Something in his walk, his somewhat accelerated pace and evident preoccupied mood, as well as a peculiar position of his extended right hand, foretold that some unusual errand had turned his steps. .h.i.therward. With considerable curiosity I endeavored to detect at a distance the specimen which he was bringing, well knowing from experience that I should soon recognize an old friend, which for sixty years had somehow managed to escape the notice of its new discoverer.

Half across the meadow I now observed that he held a leaf in his outstretched hand, and now I clearly noted that it was a compound leaf, and in another second I knew it all. For was it not a leaf of the Virginia-creeper or woodbine? and how many before him have marvelled at that strange exhibition among the woodbine leaves which had now probably met his eyes for the first time? In another moment he was at the piazza stoop, and now he appears at the studio door. Eager antic.i.p.ation and shortness of breath were equally manifest as he approached my easel and, with his right hand still outstretched towards me, exclaimed, "Well, what ails _him_?" at the same time laying down before me the mysterious specimen. It was a leaf of the woodbine, bearing along its stem a cylindrical ma.s.s of what appeared to be tiny, oblong, white eggs, all set on end, and so densely packed that but for the head and tail of the shrunken, green caterpillar which appeared at the two extremities of the ma.s.s no one would have guessed their origin. "What ails him?"

"I was sitting on my porch," continued my puzzled visitor, "and saw the white thing among the leaves, and took a closer look at it, and found it was this. I never saw anything like it before, and I thought perhaps you hadn't either, or, at least, that if you had you could tell me something about it. What ails him, anyhow?"

The story was simply told, and my readers who have followed my articles already know what the story is. We remember the strange history of those little, puzzling coc.o.o.n cl.u.s.ters on a gra.s.s stem, those "bewitched coc.o.o.ns" which gave birth to swarms of tiny wasps instead of moths, and we realize that here is more of the same sort of mischief, all of which I explained to my good neighbor, to his astonishment. How a few weeks since, when our caterpillar was much smaller than now, a tiny, black midget hovered about him, and, in spite of all his wriggling and squirming, stung him again and again, each time inserting within his body its tiny eggs. Perhaps, and probably in this case, from the number of the white tokens, more than one of the flies took a turn at the unlucky victim, for he certainly seems to have got more than his share.

"These eggs thus inserted beneath the skin of the caterpillar," I explained, "soon hatched into minute white grubs, which immediately fastened themselves upon the tissues within the caterpillar's body, and he is now obliged to eat for the whole family, which he continues to do without any outward signs of inconvenience or protest, which, of course, would be useless. I fancy he must have frequent attacks of that 'all-gone' feeling that we hear so much about in dyspeptic people, but if he does he gives no hint of it by his looks, as he devours one leaf after another along the stem, and displays his plump proportions with evident pride--like the whole tribe of h.o.r.n.y-tailed 'sphinx' caterpillars to which he belongs.

"But a few days ago he had a sudden and terrible experience. He had begun to think of retiring down among the dried leaves on the ground and spinning a coc.o.o.n, and there were bright visions of a future life filling his little green head--visions of a life on wings, as quick as thought, in an atmosphere of twilight and fragrance, and all manner of sweet indulgences. But his beautiful dream was interrupted, and probably will remain only as a dream. At one moment we see him in his prime, a perfect specimen for the 'bug-hunter' who is after the larva of _Ch.o.e.rocampa pampinatrix_. In ten minutes we look at him again: we find his body shrunken and covered with minute white grubs, all standing on their tails, which are still imbedded in his body; here one barely emerged; here another half enshrouded in a gauzy coc.o.o.n; others with their bodies bent into loops weaving the webby gauze about them, while a few hours hence all are concealed, as we see them now, in the completed long, oval, white coc.o.o.ns which still remain attached to his body."

"Well," remarked my listener, "I guess he feels pretty sick; if he don't, I vow I feel sick for him. I knew something awful ailed him, but didn't know what. I thought the things were eggs. What's the good of it all, anyhow? What do the coc.o.o.ns turn into?"

I have wished more than once that my friend could have been in my studio the day following his visit, in order to have witnessed the ocular answer to his last question. It was evident that his caterpillar specimen might have been discovered with its load of coc.o.o.ns a fortnight ago, for in the morning, upon opening the box in which I had placed him, a number of tiny black flies flew out, and several of the white coc.o.o.ns were open at the end, their dainty hinged lids thrown back. Here is one with its black midge just creeping out; others with the tiny imp peeping through the fine crevice; others with the lid still tightly closed, but with its juncture disclosing more distinctly every moment the knavery of the busy teeth within. One by one the silken lids popped up, and out flew the mischievous jack-in-the-box until within the s.p.a.ce of a few hours every coc.o.o.n was empty. So this is "what ailed him." He has been the victim of the parasitic fly known as _microgaster_.

But even now that his mortal enemies have left him, I fancy he is past encouragement or salvation. What will become of him? In his particular case he continued to dwindle and soon died, though in other instances I have known him to recover and reach the chrysalis stage, to complete his transformation into a beautiful olive and red sphinx-moth.

The Cicada's Last Song

Under the popular name of "locust," our cicada, or harvest-fly, has long enjoyed the reputation as our chief insect musician, vying with the katydid in the volume of its song. We all know its long, whizzing crescendo in the sultry summer days. But let us call things by their right names. This buzzing musician is _not_ a _locust_; it is a _cicada_. The true locust is what we ordinarily call a gra.s.shopper, that "high-elbowed grig" of the meadows, so generous with his "mola.s.ses," and with such a vigorous kick. He, too, is a musician in a modest way--a fiddler, carrying his "fiddle" on the edge of his folded wing covers, against which he gently grinds out faint, squeaky music, using his thigh-joint as a fiddle-bow. His single efforts are barely audible, but multiplied ten-thousandfold in his great field orchestra, becomes a murmur which may be distinctly heard, and which no doubt all of us have heard without a suspicion as to its source. It is a part of the great musical symphony of the harvest-fields, a roundel sustained and prolonged by the hum of bees and the buzzing of innumerable flies, and the sprightly notes of crickets, attuned to the soft murmur of breeze-blown gra.s.s. This meadow music is perceptible to any one who cares to listen for it, but it is rarely noticed. What we call the "quiet" country life, or "the quiet summer noon" of the poet, is a misnomer.

The contrast, to the observant ear, between the meadow in a hot July noon and the same meadow on a following cool and overcast day would be remarkable could we but compare the two conditions during the same moment of time. Even a cloud shadow pa.s.sing over a "quiet" meadow will often suddenly reveal to us how _noisy_ it really was but a moment before. But the harsh timbrel of the cicada is not a part of this "quiet" music. He is no retiring fiddler hiding somewhere among the gra.s.s-blades. His note rings out high above the meadow chorus, and he always gets the credit as the chief soloist, and we say, "Hark! there's a 'locust,'" when we ought to know better. Let us try and straighten out this confusion of terms, and let the younger generation at least begin the reform that shall eventually set matters right and correct this wide-spread popular error.

Our cicada belongs to quite another family of insects. Instead of jaws for biting, as our fiddling "gra.s.shopper," the cicada has only a long "beak for sucking," and this feature alone connects him with the tribe of "bugs." Moreover, his methods of music-making are very different from those of the "gra.s.shopper" tribe. It is the male only that makes the music, and his instrument is a drum. He carries two of these inclosed within his body, the opening of each being covered beneath by a broad plate, which is easily seen on the under surface of the body.

Deep within lies the "drum," and the hard and hollow body of the insect acts as a resonator or sounding-board. This drummer does not use his legs as drum-sticks, as might be supposed, his drum being vibrated by twitching muscles and cords.

The method by which the sound is produced may be ill.u.s.trated by a simple experiment. Take a small piece of stiff, sized writing-paper or smooth Manilla paper, and by pressure with some rounded blunt instrument produce a slight hollow or blister upon its surface. Upon pressure from either side this blister will be found to "snap," and could we but repeat the operation with great rapidity, a continuous sound would result. The toy called the "telegraph ticker" is made on this principle, the blister being made on a strip of steel, and the click produced by pressure upon its top, the elasticity of the metal bringing it back to its original position of rest, and each motion accompanied by a snap as the blister changes sides. Indeed, we need look no further than the bottom of almost any well-ordered tin pan for a complete ill.u.s.tration of this principle. So our cicada is a drummer, and his favorite tune is a "roll-call," the beats following each other with such rapidity as to form a tone. All through the summer we hear his strain. Even at this moment, as I write, a very long-winded specimen is tuning up in the tree just outside my studio window, and I am almost moved to give him some good advice. Have a care, my noisy minstrel. If it were I alone who were within ear-shot of your noise all might be well with you, but there are others near by to whom your music hath charms. Have a care! Only a moment ago I heard an ominous hum on my piazza, and upon investigation discovered a huge sand-hornet prying about the premises. He knows what he is looking for, and so ought you, if your parents have done their duty by you. Hereditary instinct at least ought to teach you that your drum should play second fiddle to that hornet's humming music. I remember once being the witness of the sad fate of an ancestor of yours who drummed not wisely but too well. He was monopolizing the neighborhood, just as you are doing now, when I noticed his princ.i.p.al effort was suddenly cut short in the middle in a most unusual manner. If he had been a singer I would have supposed some rival had clapped a hand over his mouth, so suddenly was the song abbreviated. In another moment there was a rustling among the leaves, as something fell from the tree in his immediate neighborhood. Down, down it dropped, its pa.s.sage to the ground accompanied by one or two short, sharp, spasmodic tattoos on that same noisy drum. The object fell among some rocks, but before I could reach the spot the humming sound of a sand-hornet greeted my ears, and in a moment more the insect took flight directly across my path, and, what was more, he was not alone. Would you know who accompanied him? Look then on the picture on page 252, and have a care, my noisy friend, for the lineal descendant of that sand-hornet now hovers outside my doorway. He has a grudge against your tribe, and he is even now on your scent. Perhaps you may be interested to know what the hornet did with that rash ancestor of yours. Well, I will tell you, for your own good. Guided by his noisy demonstration, the hornet spied him on his twig, and in a second had pounced upon him and, like a highwayman, stabbed him to the heart with a poisoned javelin. This cut short his song, as you may well suppose, and he fell in the grasp of his a.s.sailant. In another moment the hornet got a fresh hold upon him, and though your ancestor, like yourself, was much bigger than the hornet, those powerful, buzzing wings made an easy burden of him for quite a distance across the meadow. Here our captor took a rest, and after tugging that helpless cicada some distance up a high fence-rail, started off on another flight, which was brought to an end in the gra.s.s at the foot of a tree. In a moment more the hornet was seen tugging its huge load up the trunk. When some ten feet in height a third flight was made, this time gradually settling down on the roof of a shed down-hill. Tugging his game to the edge of the shed roof, a fourth trip was made, and this landed the two in the neighborhood of a sand bank at the roadside in the valley below.

A sand bank of some sort is usually the terminus of this strange ride of the cicada. Thus far many curious observers have followed the two, and wondered what it was all about. If they had cared to follow the matter to the end, they would doubtless have wondered still more at the strange fate which awaited the unlucky harvest-fly, whose last song had been his own requiem. The sand-hornet is also known as the "digger-wasp," the largest of its kind, the most formidable of all our hornets, and carrying within its black, yellow-spotted body a most searching and terrible poisoned sting. It was a common belief in ancient times that "seventeen p.r.i.c.ks of a hornet" would "kill a man,"

to quote from Pliny; and there are many country people to-day who would as quickly attack a rattlesnake as this big sand-hornet, and who "absolutely know" of men who have been "knocked down" and even "killed" by one stab of its sting. However this may be, it is well to keep at a respectful distance. When we know what the little yellow-jacket can do with its tiny dagger, and then reflect that this sand-hornet's javelin is about a third of an inch long, we can draw our own conclusions, and will readily understand why it was that our cicada's song was cut short. "But why didn't the hornet eat him on the spot? Why should it fly away with him and yank him about so unmercifully?" This is a common question with those who have observed the episode above described. A visit to the sand bank would have explained the object of it all. The exposed surface is seen to be perforated here and there with holes as large as one's little finger, while from one of them an occasional tiny stream of sand pours out, and we catch a glimpse of the h.o.r.n.y, spiked legs of the digger-wasp within. Even as we observe him closely a loud hum is heard, and a filmy, buzzing object falls precipitately upon the bank, and in the jumble of wings and black bodies we now distinguish our hornet and cicada, which only a moment before had started from the edge of the shed roof above. The cicada is apparently dead, and is now an easy prey as the wasp lugs him to the mouth of one of the burrows, and soon disappears in its depths.

Further than this few have followed the couple. But Professor C. V.

Riley, our government entomologist, has unearthed the entire mystery, and eye-witnessed the fate of our cicada, and I am thus enabled to picture the rest of the tragedy. What now follows is very similar to what I described in a previous paper concerning the mud-wasp nest packed with its dead spiders. Our cicada is not dead--more's the pity.

The thrust of the sting has only paralyzed the insect, in order that the young of the hornet may be provided with _living_ food. From the opening of the tunnel in the sand our harvest-fly was lugged a distance of about six inches, when the tunnel branched in various directions. Down a branch for about eight inches more, and his journey terminated in a dungeon, where his career was doomed to end. Doubtless each of the other branches held one or two similar prisoners, for the cicada is the favorite prey of this particular wasp. Once arrived at the dungeon, the hornet deposits an egg upon its victim, and leaves him in its charge. In a few days it hatches into a larva with such a voracious appet.i.te that within a week it has devoured the contents of the cicada's sh.e.l.l and reached its full growth. It now incloses itself within a silky coc.o.o.n, and after abiding the winter emerges at the brim in the spring a full-fledged hornet, with its mouth watering at the thought of cicadas.

What a strange wonder-working medicine is this which the hornet carries in its laboratory! In the guise of death it yet prolongs life indefinitely. The ordinary existence of the cicada, for instance, is but a few weeks at most, and yet it is claimed by Mr. Riley that if for any reason the egg of the wasp should fail to hatch, the paralyzed cicada will remain in its condition of suspended animation for a year, and presumably longer.

Here is a suggestion for the materia medica which may open up immortal fame to the chemist of the future. What is this mysterious essence which the wasp carries in its poniard? As Professor Riley suggestively remarks, "If man could do what these wasps have done from time immemorial, viz., preserve for an indefinite period the animals they feed on by the simple insertion of some toxic fluid in the tissues, he would be able to revolutionize the present methods of shipping cattle and sheep, and obviate much of the cruelty which now attends the transportation of live-stock and much of the expense involved in cold storage."