Upon looking through the instrument, we find the fluid swarming with animals of various shapes and magnitudes.  Some are darting through the water with great rapidity, while others are pursuing and devouring creatures more infinitesimal than themselves.  Many are attached to the twig by long delicate threads, several have their bodies inclosed in a transparent tube, from one end of which the animal partly protrudes and then recedes, while others are covered by an elegant shell or case.  The minutest kinds, many of which are so small that millions might be contained in a single drop of water, appear like mere animated globules, free, single, and of various colours, sporting about in every direction.  Numerous species resemble pearly or opaline cups or vases, fringed round the margin with delicate fibres, that are in constant oscillation.  Some of these are attached by spiral tendrils; others are united by a slender stem to one common trunk, appearing like a bunch of hare-bells; others are of a globular form, and grouped together in a definite pattern, on a tabular or spherical membranous case, for a certain period of their existence, and ultimately become detached and locomotive, while many are permanently clustered together, and die if separated from the parent mass.  They have no organs of progressive motion, similar to those of beasts, birds, or fishes; and though many species are destitute of eyes, yet possess an accurate perception of the presence of other bodies, and pursue and capture their prey with unerring purpose.

[Illustration:  FOOT OF COMMON HOUSE-FLY.]

[Illustration:  HAIR, GREATLY MAGNIFIED.
  A. Hairs of the Bat. 
  B. Of the Mole. 
  C. Of the Mouse.]

Mantell’s Thoughts on Animalcules.

* * * * *

THE CANARY.

This bird, which is now kept and reared throughout the whole of Europe, and even in Russia and Siberia, on account of its pretty form, docility, and sweet song, is a native of the Canary Isles.  On the banks of small streams, in the pleasant valleys of those lovely islands, it builds its nest in the branches of the orange-trees, of which it is so fond, that even in this country the bird has been known to find its way into the greenhouse, and select the fork of one of the branches of an orange-tree on which to build its nest, seeming to be pleased with the sweet perfume of the blossoms.

[Illustration:  CANARY.]

The bird has been known in Europe since the beginning of the sixteenth century, when a ship, having a large number of canaries on board destined for Leghorn, was wrecked on the coast of Italy.  The birds having regained their liberty, flew to the nearest land, which happened to be the island of Elba, where they found so mild a climate that they built their nests there and became very numerous.  But the desire to possess such beautiful songsters led to