# The How and Why Library/Insects/Section I

PART III—INSECTS, ETC.
I. MRS. MUSCA DOMESTICA CALLS
"Were you speaking of me? Here I am."
A very dignified little visitor, about a quarter of an inch long, drops "out of the nowhere" in the most surprising way! But she is very polite about ringing a little buzzing door bell to let you know she is coming. "Buzz-z-zip! I'm Mrs. Musca Domestica!"
What a name for such a little creature! One of the capital letters of it would almost cover her, and the length of it would make a nice distance for an evening stroll.
"It's just Latin for House Fly," she says. "Don't you think I deserve it? I come into the house whenever you leave the screen door open. I'm neighborly and don't wait to be invited. I'm very fond of human society. You have such nice things to eat. But you are not very friendly," she added reproachfully. "Actually, I've had the door shut in my face, and been 'shoo-ed' out like a hen." A house fly magnified.
"Well, you're not very clean, you know. You go to dirty places, and you don't wipe your feet."
"I would if I had a door-mat, I would, indeed. I wash my face and brush my clothes oftener than you do. Just watch me."
There she sits at a respectful distance, rubbing her little front hairy legs together vigorously. Then she balances herself on the other four, and rubs the hindlegs. When the middle pair are cleaned, she draws a leg across her mouth to wet it, and washes her face like a cat. Finally she flutters her silver gauze wings to shake the dust off. As a delicate hint she nibbles at a clean plate.
"Don't human people ask their visitors if they care for refreshments? Thank you! A grain of sugar is my favorite lunch. You may watch me eat, if you won't come too near."
She has no legs to spare for picking up food; but she has a little mouth that drops like an elephant's trunk. Out of that mouth comes a dew-drop of liquid to make syrup of the grain of sugar. The knob on the end of the mouth parts, and the two lips spread out flat over that drop. She stands there licking with a little rasp of a tongue blissfully until she has sucked it all up. Then she wipes her mouth with her foot, and cleans herself all over again. Tsetse Fly, found in Africa. Its bite kills cattle, horses and dogs, but is harmless to man.
"I have another name. It's Diptera. That means two-winged. My family is very important. It's the biggest one on earth, with thousands of members. You can always know a Diptera by the two wings. Most insects have four. One of my cousins is very musical, but I am sorry to say, he is also a blood-sucker. If he shows any fondness for people, it's because he likes to bite them. His name is mosquito. The horse-, or gad-fly, can make horses jump and even run away. The Hessian fly stings wheat. The saw fly lays her eggs on rose blossoms. The tsetse fly kills cattle sometimes; the gall fly stings plants and makes galls grow on them. And there are gnats and midges. They come in swarms. Did you ever hear of 'a plague of flies?'" Ichneumon Fly; is useful because it destroys insects which injure trees and shrubs.
"Yes, indeed, and 'the fly in the ointment.' You spoil a good many things. Your whole family seems to be a nuisance."
"Not all. The dragon-fly and ichneumon fly are useful. And I don't see what you have against me! I can't bite or sting, and I eat very little, compared with some people I could mention. To be sure, I have little tickly hairs on my feet and scrapers on my tongue, and that makes people nervous. And I like to wake lazy people up in the morning. No one can sleep after daylight when I'm around. If you had only one summer to live, you'd want to get up early and make the most of every day.
"It's pretty hard to catch me, too. I have several thousand little flat eyes in the two in my head. They're like the facets on adiamond, only ever so many more of them. I can feel, and I can smell food with these two feather plumes on my head.
"No, indeed, I never fold my wings, when I sit down, as foolish moths do. I keep them ready for business. Aren't they pretty? I make them of silver gauze, and paint them with bronze and purple. Do you notice cream-tinted scales behind them? Those are balancers. If I didn't have them I'd tumble head over heels when I tried to fly. I can tilt my head, too. It is set right down on my shoulders, on a kind of pivot.
"No, I never have dyspepsia, thank you! You see, I make syrup or broth out of everything I eat. The food goes into a little mill, with spiny teeth, to be chewed and mixed with something to digest it. Then it goes into a little bag of a stomach. I can tell you how not to have lung troubles, too. Don't have any lungs. I breathe through holes in my skin like the leaves on the trees. I fill little air bladders and pass the air back to blood vessels. A fly's foot magnified.
"If you really want to know how wonderfully I am made you ought to have a glass that would magnify me a hundred times. I have three silver girdles across my chest, or thorax, a yellow band on my abdomen and some golden spots. All six of my legs are fastened to the thorax. But if there is one thing I am vain of it's my feet. Just look at them. The legs are jointed, and on the last joint of each is a pair of claws like a lobster's. But they close over a pad or cushion covered with knobby hairs. All those hairs are sticky, and cling to things. Really, the smoother you make your walls the better I like them. A gold picture frame, or a nice white gas globe just suits me for an evening stroll, or a bed to sleep on, upside down. But every thing sticks to those feet! I can't keep them clean, although I wipe them on every bit of bread or food you leave out for door-mats."
"Ah, so that's why you bring typhoid fever into the house, naughty fly!"
"Well!" with a little bristle of wings. "No wonder! You ought to see where I have to bring up my babies. I can't carry them around, all legs and no arms as I am, now can I? I have to lay my eggs in warm moist places around stables and in garbage cans, orthey never would hatch or have anything to eat. You never see those eggs. They are dull, chalky seed-looking, little things, buried in smelly places. They hatch out into little white squirmy larvae in twenty-four hours, and eat that decaying stuff. I wouldn't touch it myself! I like the good things on human tables. In less than a week those babies grow as long as I, and shut themselves up in brown cradles.
"Asleep? You wouldn't think so, from all the things that happen in a week's time. Why, they make themselves all over, from little white, crawly, unpleasant grubs into—"
"Beautiful little winged creatures like their mother?"
"Not just at once. When they push the front ends of their cradles off and crawl out, their wings are very small and soft and baggy, and cling close to their sides. Those infant flies are pale and sickly looking. You wouldn't think them likely to live. And they breathe by puffing out their foreheads in the most comical way. I assure you I don't always know my own children.
"Do I have many children? Oh, quite a few. I never keep any account of them. I lay something near a hundred eggs at a time and four times in a season. In just fourteen days after an egg is laid it is hatched, eats, grows, makes a cradle, comes out and is a full-grown fly ready to lay eggs itself. I shouldn't wonder if I would be several times a great grandmother before I die. I'm not saying it to brag. It's a trait of the whole Diptera family."
"Mercy, no wonder there are so many of you!" Mrs. Musca Domestica rubbed her clothes brush legs together, thoughtfully, and washed her face for the third time.
"There are not as many house flies as there used to be. We really threaten to die out. People don't leave as many piles of refuse about for us to lay eggs in. They scald their garbage cans, put lime in plumbing traps, and actually wash stable floors with hose. There are screen doors and windows everywhere. If we do get into a house, there are fly traps and sticky paper to catch us. In some houses there isn't a crumb about. I really wonder such stingy people don't starve themselves. We have other troubles, too. Most of us die of a kind of fungus that paralyzes us, in the fall. Haven't you seen us sitting around, unable to move, with gray bands around our bodies? A few of us do manage to creep into cracks of warm houses, and go to sleep until spring. And there is—
"Did you say spiders??? "Good-by!!!"
See Fly, page 687