CHILD is thrilled with fairy stories of ogres in their dens, with the bones of their victims strewn around. The ants have real ogres, but luckily, they do not know about it and so cannot suffer from agonizing fears. The ant ogres seem to have depended upon the fact that the ant is so absorbed in her work that she carries her booty up hill and down dale with small regard for the topography of the country. Thus they build their pits, with instinctive faith that they will some day be entered by these creatures, obsessed by industry and careless of what lies in the path. The pits vary with the size of the ogre at the bottom; there are as many sized pits as are beds in the story of Golden Locks and the bears; often the pits are not more than an inch across, or even less, while others are two inches in diameter. They are always made in sandy or crumbly soil and in a place protected from wind and rain; they vary in depth in proportion to their width, for the slope is always as steep as the soil will stand without slipping.
All that can be seen of the ogre at the bottom, is a pair of long, curved jaws, looking innocent enough at the very center of the pit. If we dig the creature out, we find it a comical looking insect. It is humpbacked, with a big, spindle-shaped abdomen; from its great awkward body projects a flat, sneaking looking head, armed in front with the sickle jaws which are spiny and bristly near the base, and smooth, sharp and curved at the tip. The strange thing about these jaws is that they lead directly to the throat, since the ant-lion has no mouth. Each jaw is made up of two pieces which are grooved where they join and thus form a tube with a hole in the tip through which the industrious blood of the ants can be sucked; not only do the sharp sickle points hold the victim, but there are three teeth along the side of each jaw to help with this. The two front pairs of legs are small and spiny; the hind legs are strong and peculiarly twisted, and have a sharp spikelike claw at the end, which is so arranged as to push the insect backward vigorously if occasion requires; in fact, the ant-lion in walking about, moves more naturally backward than forward because of the peculiar structure of his legs.
Ant-lion with its cocoon and larva.
Having studied the ogre, we can see better how he manages to trap his victim. As the ant goes scurrying along, she rushes over the edge of the pit and at once begins to slide downward; she is frightened and struggles to get back; just then a jet of sand, aimed well from the bottom of the pit, hits her and knocks her back. She still struggles, and there follows a fusillade of sand jets, each hitting her from above and knocking her down to the fatal center where the sickle jaws await her and are promptly thrust into her; if she is large and still struggles, the big, unwieldy body of the ogre, buried in the sand, anchors him fast and his peculiar, crooked hind legs push his body backward in this strange tug of war; thus, the ant-ogre is not dragged out of his den by the struggles of the ant, and soon the loss of blood weakens her and she shrivels up.
The secret of the jets of sand, lies in the flat head of the ogre; if we look at it regarding it as a shovel, we can see that it is well fitted for its purpose; for it is a shovel with a strong mechanism working it. In fact, the whole pit is dug with this shovel head. Wonderful stories are told about the way that ant-lions dig their pits, marking out the outer margin in a circle, and working inward. However, our common ant-lion of the East simply digs down into the sand and flips the sand out until it makes a pit. If an ant-lion can be caught and put in a jar of sand it will soon make its pit, and the process may be noted carefully.
There is one quality in the ogre which merits praise, and that is his patience. There he lies in his hole for days or perhaps weeks, with nothing to eat and no ant coming that way; so when we see an absent-minded ant scrambling over into the pit, let us think of the empty stomach of this patient little engineer which has constructed his pit with such accuracy and so much labor. So precarious is the living picked up by the ant-lions, that it may require one, two or three years to bring one to maturity. At that time it makes a perfectly globular cocoon of silk and sand, the size of a large pea, and within it, changes to a pupa; and when finally ready to emerge, the pupa pushes itself part way out of the cocoon and the skin is shed and left at the cocoon door. The adult resembles a small dragon-fly; it has large net-veined wings and is a most graceful insect, as different as can be from the humpbacked ogre which it once was—a transformation quite as marvelous as that which occurred in Beauty and the Beast. Throughout the Middle West, the ant-lion in its pit is called the "doodle-bug."
Reference—Manual for Study of Insects, Comstock.
Leading thought—The ant-lion, or "doodle-bug" makes a little pit in the sand with very steep sides, and hidden at the bottom of it, waits for ants to tumble in to be seized by its waiting jaws. Later the ant-lion changes to a beautiful insect with gauzy wings, resembling a small dragon-fly.
Method—The pupils should see the ant-lion pits in their natural situations, but the insects may be studied in the schoolroom. Some of the ant-lions may be dug out of their pits and placed in a dish of sand. They will soon make their pits, and may be watched during this interesting process. It is hardly advisable to try to rear these insects, as they may require two or three years for development.
1. Where were the ant-lion pits out of doors? Were they in a windy place? Were they in a place protected from storms? In what kind of soil were they made?
2. Measure one of the pits. How broad across, and how deep? Are all the pits of the same size? Why?
3. What can you see as you look down into the ant-lion's pit? Roll a tiny pebble in and see what happens. Watch until an ant comes hurrying along and slips into the pit. What happens then? As she struggles to get out how is she knocked back in? What happens to her if she falls to the bottom?
4. Take a trowel and dig out the doodle-bug. What is the shape of its body? What part of the insect did you see at the bottom of the pit? Do you know that these great sickle-shaped jaws are hollow tubes for sucking blood? Does the ant-lion eat anything except the blood of its victim?
5. Can you see that the ant-lion moves backward more easily than forward? How are its hind legs formed to help push it backward? How does this help the ant-lion in holding its prey? How does the big awkward body of the ant-lion help to hold it in place at the bottom of the pit when it seizes an ant in its jaws?
6. What shape is the ant-lion's head? How does it use this head in taking its prey? In digging its pit?
7. Take a doodle-bug to the schoolroom, place it in a dish of sand, covered with glass, and watch it build its pit.
8. Read in the entomological books about the cocoon of the ant-lion and what the adult looks like, and then write an ant-lion autobiography.
Supplementary reading—Insect Stories, Kellogg, "The True Story of Morrowbie Jukes."