difference on the part of the caterpillars, who go right on feeding. But I can't see any cause for such antics."

"Hal, take this smaller glass," the Doctor said; "you will have to get closer to the leaf, and you will not see so big an area at once; but it is more powerful than the other. Now I will tell you both what to look for, and I think then you will understand this performance, which is one of the most interesting in the insect world. Now look at one of the caterpillars, and you will see that near the hinder end of each, and right on top, there are little tubes projecting upward, and then you will notice that it is always to this end that the ant approaches with its pats and caresses. Watch one of the ants very carefully, now. Doesn't it pat with its antennæ, or feelers, right on or around those tubes?

"Now watch the upper end of the tube, and you'll see a little drop of a honey-yellow fluid appear there; and it will then be easy enough, when you see the ant suck up all this fluid and run off to repeat this performance with another caterpillar, to understand what the bond of friendship is. For these caterpillars are simply the cows of the ants, and the thick, gummy, and very sweet fluid which then exudes from those tiny tubes is a sort of honey-milk on which these ants mainly subsist, and their antennæ are simply used in this way to milk their caterpillar cattle."

As the Doctor finished speaking, both boys looked up

from the colonies of caterpillars they had been watching, and Ned eagerly asked,

"But where do the cows' come in? I can see that this is very nice for the ants, but I don't see what the caterpillars gain by it all."

"If you boys will find me two or three ladybugs,' or other specimens of the family of beetles, I will soon prove to you that the caterpillars are even greater gainers than the ants by this friendship," the Doctor replied. And as they went off, looking over the leaves and twigs of bushes for what they wanted, he deftly picked some of the caterpillars off the leaves with his forceps, and deposited them in a pill-box, which he placed in his pocket.

In a few minutes each of the boys was back with two or three ladybugs; and taking one of these the Doctor carefully dropped it into the pill-box in which were the caterpillars, holding it so that both boys could watch the result. No sooner had the beetle touched the bottom of the box than it grabbed one of the caterpillars, and fastening one of its hard jaws in the fleshy sides of the helpless creature, began to extract the life juices from it. Then taking another beetle, he carefully held it over a leaf whereon were a large number of caterpillars being guarded by a score or more of ants, and gently dropped it.

Again the beetle made a rush for a caterpillar, but it

was not so quick as a dozen ants, which rushed for it and began so savagely attacking it that the poor ladybug, after trying to fly away with its burden of biting and tearing ants, relinquished its hold upon the leaf and rolled to the ground, where it was no better off, as Harry discovered, reporting that the ants were tearing it to pieces while he watched them with the glass. This experiment the Doctor made several times, and in each case the result was the same, save in one, where the ladybug, evidently knowing what to expect, quickly flew away before the ants could reach it, and without paying any attention to the caterpillars.

"How long do you think this species of caterpillar would last if they did not have the ants to defend them?” the Doctor asked.

"Not very long, I am sure!" Ned replied. "This is really the most wonderful thing. Why don't we have such wonderful species at home, Doctor? Why are they all in the warm country?"

"They are not," was the reply. "There are two species of this same genus of butterflies in your own State, Pennsylvania, which are shielded from harm by ants, and there are a number of species of plant lice and of tree hoppers that are also protected in the same way. It is common everywhere, yet there are few who observe so carefully as ever to have seen it."

A storm had been raging from the northeast all day. Toward evening the wind strengthened to a gale, and the fine, icy snow swirled and drifted over the frozen fields.

I lay a long time listening to the wild symphony of the winds, thankful for the roof over my head, and wondering how the hungry, homeless creatures out of doors would pass the night. Where do the birds sleep such nights as this? Where in this bitter cold, this darkness they make their beds? The lark that snow at my feet as I crossed the pasture where will it sleep to-night?

and storm, will

broke from the

this afternoon

The storm grew fiercer; the wind roared through the big pines by the side of the house and swept hoarsely on across the fields; the pines shivered and groaned and their long limbs scraped over the shingles above me as if

feeling with frozen fingers for a way in; the windows rattled, the cracks and corners of the old farm-house shrieked, and a long, thin line of snow sifted in from beneath the window across the garret floor.

I fancied these sounds of the storm were the voices of freezing birds, crying to be taken in from the cold. Once I thought I heard a thud against the window, a sound heavier than the rattle of the snow. Something seemed to be beating the glass. It might be a bird. I got out of bed to look; but there was only the ghostly face of the snow pressed against the panes, halfway to the window's top. I imagined that I heard the thud again; but while listening, fell asleep and dreamed that my window was frozen fast, and that all the birds in the world were knocking at it, trying to get in out of the night and

storm.

The fields lay pure and white and flooded with sunshine when I awoke. Jumping out of bed, I ran to the window, and saw a dark object on the sill outside. I raised the sash, and there, close against the glass, were two quails frozen stiff in the snow. It was they I heard the night before fluttering at the window. The ground had been covered deep with snow for several days, and at last, driven by hunger and cold from the fields, they saw my light, and sought shelter from the storm and a bed for the night with me.