officer. It is however but justice to observe that a similar spirit of improvement is obvious in the other branches of Natural History, and that the entire establishment is rapidly becoming an honour to the country in which we live.

THE

GRAMMAR

OF

ENTOMOLOGY.

BOOK III.

PHYSIOLOGY OR ANATOMY OF INSECTS.

To trace in Nature's most minute design
The signature and stamp of power divine;
Contrivance intricate expressed with ease,
Where unassisted sight no beauty sees;
The shapely limb, the lubricated joint,
Within the small dimensions of a point,
Muscle and nerve miraculously spun,-
His mighty work, who speaks, and it is done.

COWPER.

Skeleton of a large Water Beetle, as seen from below. B, the head. DD, the prothorax. FF, the mesothorax. HH, the metathorax. a a, fore legs. e e, fore wings. ii, middle legs. o o, hind wings. u u, hind legs. y, antennæ.

CHAPTER I.

THE Physiology of Insects is the account of how they are made: there are in every animal four essential elements,— matter, motion, sensation, and mind.

Matter is inert-it does not move by its own powers; it is tangible- the touch ascertains that it resists: matter in animals has various degrees of consistency; convenience, however, has suggested its division into solid and fluid.

Matter, chiefly in its solid form, is the element of which the systems of organs are composed; and organs are the instruments by which functions are performed: in all animals there are seven systems of organs to perform seven series of functions. The seven systems of organs and their respective functions are these:-bones, for support; muscles, for motion; air-tubes, for respiration; blood-vessels, for circulation; alimentary canal for digestion; nerves, for sensation; and the organs of the sexes, for reproduction. The fluids in insects are blood and various secretions: the blood is supplied by nutriment transmitted from the alimentary canal: the solid parts are renewed by secretions from the blood.

Motion, in the animal frame, is of two kinds; dominant motion, which acknowledges not the authority of the mind; for instance, circulation of the blood: and subservient motion, which operates only in accordance with the behests of mind.

Sensation is the ultimate power of matter so perfected as to take cognizance of facts beyond the limits of the body: sensation is of two kinds; that derived from external objects, which appears the aim of animal life, and conduces to its maintenance, and that which conveys information from matter to mind, and behest from mind to matter.

Mind is the commanding element; the other elements in acting obey it, but in existence and characters are independent of it: no powers of mind can prevent the existence, or change the characters of matter, motion, or sensation: mind argues, then commands; it takes cognizance of causes, and provides for consequent effects, before the other elements can obey its behests. The great powers of mind are speculation and retention: speculation is the power which supposes an event that has not yet occurred;