FRY OF SWAN-MUSSEL, HIGHLY MAGNIFIED.
This particular mollusc is known by the name of swan-mussel; the young fry are sent into the water in April and May. There is another kind of fresh-water mussel in rivers and streams, called the pearl-mussel, pearls being occasionally found in them. I had one of these pearls once given me by a lad, taken from a river in the Isle of Man. I took it to a jeweller, in Liverpool, who valued it at a guinea. Your uncle Arthur, to whom I gave it, had it set in gold as a pin "I wish," said May, who had listened to this part of the story with great attention, "I wish pearl-mussels would live in the canal, it would be so nice to get the pearls out of them." Very few mussels are found to contain the pearls; perhaps you might have to open many hundreds before you found a single pearl, and I should not like to cause the death of so many harmless animals for the sake of a single pearl.
FRESH-WATER MUSSEL.
"Here is another swan-mussel, and, just look, papa," said Jack, "some other shells are fastened on it." So there are; it is a lot of the curious and pretty little zebra-mussel. How prettily they are marked with zig-zag stripes of reddish brown, especially the young specimens. The name of mussel is better suited to these molluscs than to the large kinds upon which the "zebras" are often attached, because, like the salt water mussel you have often seen at New Brighton, they have the power of spinning, what is called, "a byssus"—here, you see, is the substance I mean—by which they fasten themselves to shells, or to stones, roots, and other things.
ZEBRA MUSSEL.—b. BYSSUS.
There flies one of those pretty little birds, the long-tailed titmouse; it is common enough, certainly, but I never fail to notice several upon the hedges and poplar trees of the "Duke's drive." There are several members of the titmouse family found in Great Britain; let me count them. First we have the great tit, then the little blue-tit, the long-tailed tit, the cole tit, the marsh, the crested and the bearded tit. How many does that make? Seven; but the crested tit is very uncommon, and the bearded tit does not occur in Shropshire. The other five are quite common and we shall, I dare say, be able to see all in the course of to-day's walk. The long-tailed tit, so called on account of the great length of the tail feathers, is a very active, lively little bird. Indeed, activity and liveliness belong to all the tit family. See how the little fellow flits from branch to branch, seldom remaining long on one spot. It is a very small bird, almost the smallest British bird we have; of course I am thinking of the tit's body and not taking into account its tail. The skin is remarkably tender, and thin as tissue paper. Like all the titmice, the long-tailed tit feeds on insects and their larvæ. I do not remember to have heard or seen this species tapping the bark of a tree with its beak, as the great and the blue tit are frequently in the habit of doing, but most probably they do the same. "What do they tap for, papa?" asked May. I suppose for the purpose of frightening the tiny insects, which lurk under the bark, from their hiding places, when they quickly snap them up with their sharply-pointed bills and devour them. "Is not this the tit which the people about here call a bottle tit, and which makes a very beautiful nest?" asked Willy. Yes, the nest is indeed a very pretty object, and one that you would never, I think, confuse with the nest of any other bird. The outside is formed of that white-coloured lichen, so pretty and so common, and moss, and if you were to put your finger, May, into the inside, which is full of the softest feathers, you would say it was as nice as your own muff. The nest is oval, with a hole at the side. I believe that sometimes two holes exist, but I have never seen two in a nest. The eggs are very small, and are white with a few lilac spots. As many as a dozen or more are sometimes found in a nest.
LONG-TAILED TIT.