known, when hunted, to crouch exposed upon a rock o nearly its own colour, in the midst of a river, and so to evade detection by its pursuers; and we perpetually hear such cases brought forward as decisive proofs of its extreme sagacity. However, as regards the latter instance, will not a brood of newly hatched partridges instantly cower and squat motionless at sight of a foe? and, as concerns the former, do we not find that many beetles, though just emerged from the pupa state, will simulate death every bit as cleverly as a fox or corn-crake? Whence it surely follows that there can be no occasion to attribute the act to a reasoning process in the one animal, any more than in the other.

It would be unnecessary to enter here into any details on the obvious correlativeness of the dominant instincts of animals to the mode of life most congenial to their constitution, to remark on the mutual relations of habit and structure, and the exquisite adaptation of structure to locality. Hence, the natural habits of species of necessity bear reference to their indigenous haunts, as manifestly as their structural conformation. Thus, the elephant, which, like the other great Pachydérmata, affects the vicinity of rivers and marshes, delights to relax its rigid hide in the stream; and afterwards covers it with a thick plastering of mud, probably to retard its too rapid desiccation: the which has been deemed an incontrovertible proof of its reasoning from observation. A young robin, however, the first time that it sees water, will, if it be not too deep, fearlessly plunge in and wash; and a young wren or lark will avail itself of the earliest opportunity to dust its feathers on the ground, the exact purport of which is not yet definitely understood. If, therefore, the latter be thus obviously instinctive, what reason have we to esteem the former otherwise? The uniformity of all these habits and propensities, in creatures of the same species, tends rather to intimate that in neither case are they the result of reasoning.

To infer reflection on the part of brutes, as many have not scrupled to do, as the motive for whatever in human actions. could only be the result of reasoning, one would imagine to be too palpable a misapprehension to need serious consideration; yet some writers have gone so far as to attribute forethought to the dormouse, and other species which provide

I have noticed a remarkable instance of this, on placing down a stuffed polecat before a young brood, tended by a bantam hen. A rail or gallinule will also run towards a bank approximating to their own colour; and, if no hiding-place be discoverable, will insert the head into a crevice, and, remaining motionless, suffer themselves to be taken. Of this I have known many instances.

instinctively against the winter season.* Perhaps it might be deemed a sufficient overthrow to this most shallow notion, to call in mind the migrative impulse; to enquire how the untaught cuckoo (raised by permanently resident fosterparents) could reason that in another clime it should escape the rigours of a season that it had never experienced? But herein we have an additional principle involved, which will require a separate consideration. Proceed we, then, to examine into the presumed sagacity of those provident creatures, as the ant and harvest mouse, that habitually lay up a store for future need, and even provide against all possible injury from germination, by carefully nibbling out the corcule from each grain. Can any thing be more truly wonderful as a matter of instinct? All instincts are, indeed, equally wonderful. But it would certainly be even more extraordinary, if every member of these species were to be alike induced to pursue the same course by a process of reasoning. The following anecdotes will suffice to probe the intellect of these animals: I have a tame squirrel, which, though regularly fed all its life from day to day, nevertheless displays the intuitive habit of its race, in always hoarding the superfluities of its food. Now, in its mode of effecting this, a superficial observer might fancy that he discerned a fair share of intelligence. Carrying a nut, for instance, in its mouth, it scrapes a hole with its fore paws in the litter at the bottom of its cage; and then, after depositing its burthen, scratches together the hay, or whatever it may be, over it, and pats it down with its paws. Moreover, it never fails to remember the spot, and will occasionally, when not wishing for food, examine the place to ascertain whether it be safe. But mark the sequel. I have repeatedly seen the same animal act precisely thus on the bare carpet, and upon a smooth mahogany table; yes, upon a table I have frequently seen it deposit its nut, give it a few quick pats down, and finally thus leave it wholly unconcealed. The tits (Pàri), also, evince a like propensity of hiding food, one of their many resemblances to the

* See Mag. Nat. Hist. (old series), vol. ix. p. 611. 1. 15.

+ It is no new remark, that rodents are much below the Carnívora in the scale of intelligence; a necessary consequence of their inferiorly developed brain. Yet few animals have more instinctive cunning and resource than the common rat: but this is not intellect, of which it displays scarcely any when brought up tame; a condition which, as will be shown, is sure to call forth the non-instinctive intelligence of animals. Judging from my own observation, I should say that the rat was mentally superior to the house mouse, but inferior to the squirrel; which, in its turn, must yield in intellect to the hare; and, I believe, the comparative structure of their brains will be found in accordance.

Corvida; and a tame marsh tit that I once possessed used habitually to drop the remainder of the almond, or piece of suet, that he had been picking, into the water-glass attached to the cage, although he never could thence reobtain it, and though his water was thus daily rendered turbid. I could narrate analogous instances without number.

Thus it plainly appears, that the instinct of each animal is adapted to its proper sphere; for the mode of life it was destined to pursue, and for that only. With this restriction (if such it can be called), it is in each case perfect. The actions of every creature uncontrolled and uninfluenced by man are invariably such as tend to the general welfare of its species; sometimes collectively, however, rather than individually* (whence we hear of what have been termed "mistakes of instinct"). They evince superhuman wisdom, because it is innate, and, therefore, instilled by an all-wise Creator. Indeed, the unpremeditated resource of animals, in cases of emergency, is oftentimes decidedly superior to that of man; and why? Because they need not experience for their guide, but are prompted to act aright by intuition.

In wild nature, this inborn knowledge of brutes thus abundantly sufficing for the attainment of all they require, there is, in consequence, but little to stimulate the exercise of their reflective faculties; and, accordingly, their general agency may be considered as passive, in effect analogous to the operation of the laws of matter. Even the "half-reasoning elephant," in the wild woods, is but a creature of unreflecting impulse, to an extent which wholly dissevers it from all community of mental attribute with the lowest grade of mankind. Witness the subdued tamed animal, which, travelling along its accustomed route, suddenly broke loose from its attendants, affrighted at the near yell of a tiger. At once its former submissiveness was forgotten: it rejoined the wild troops, and was again a free tenant of the jungle. Years rolled on, and it was retaken by the ordinary method. The sight of the stakes never sufficed to awaken its recollection; nor did the mode employed to secure it when entrapped. It was sullen and savage, and acted in nowise differently from its companions. By chance, however, its former keeper was present, who, after a while, recognised the animal. He gave the word of command, and it was instantly submissive; all traces of its wild nature suddenly dissipated; its previous habits were forgotten; it was once more a reclaimed animal,

* As in the contests of animals for the other sex; whence it follows that the breed is chiefly transmitted by the most stout and healthy.

and suffered itself to be led tractably to its place of confinement. * Would a rational being have acted like this elephant?

(To be continued.)

ART. II. An Estimate of the probable Degrees of Temperature in Europe during the Tertiary Periods; founded upon the Study of Fossil Shells: By M. G. P. DESHAYES. Read to the French Academy, May 23. 1836.

(From the Annales des Sciences Naturelles.)

CONCHOLOGY, studied in a logical manner in its various relations both to zoology and geology, may become a powerful means of bringing this latter science to perfection. It is even allowable, in the present day, to anticipate the time when conchology shall arrive at questions which relate to the general physics of the terrestrial globe, and furnish us with the necessary materials for their solution.

Very numerous observations, repeated upon more than eight thousand species of recent and fossil shells, and these, again, multiplied upon more than sixty thousand individuals of all regions, have enabled me to perceive important consequences with regard to an approximate estimate of the temperatures of the geological periods, concerning which man cannot cite his historical annals, since he then had no existence upon the surface of the earth.

If vegetables, as M. Arago has learnedly established in the Annuaire du Bureau des Longitudes for 1834, can give the mean temperatures of the historic period; if the existence in certain places of the vine, the palm, &c., are, to the skilful naturalist, equivalent to thermometrical observations; I think that animals also, and especially those which people the waters of the ocean, may by their presence determine very nearly the mean temperature of the place they inhabit.

All marine animals are not adapted to indicate temperature with the same precision: we must choose those which, possessed of but small powers of motion, cannot withdraw themselves periodically from the changes of the seasons, and are obliged to sustain all their influence in the places which have given them birth. The greatest number of the Mollusca and Zoophytes answer to this description.

To arrive at a knowledge of the temperatures of periods antecedent to human existence, there is a chain of reasoning to follow. We must first seek a starting point in existing na

* I shall have occasion to revert to this presently.

ture, to ascertain if the life of those animals concerning, which we are about to enquire, be connected more or less intimately with circumstances among which climate may be the most essential. This induces me briefly to state sonie facts relating to the distribution of Mollúsca, proceeding from north to south; and, in order to shorten it, I will only speak of those which extend from Cape North to the Gulf of Guinea. If we take all together the small number of species which inhabit the north, we may divide them into two very distinct groups: first, those peculiar to the icy regions, and which never pass their limits; and, secondly, a smaller number, which exist also in the temperate seas of Germany, France, and England, with the species belonging to those seas.

In examining the Mollusca of our temperate seas, in which there exists a greater number of species than in those of the north, it is easy to separate them into three series. In the first are comprised the species which I have just pointed out as being common to the temperate and northern seas; the species of the second series extend also as far as the south seas; those of the third are peculiar to the temperate seas.

Let us now turn to the region between the tropics, and we shall observe similar phenomena: we shall find there a greater number of species than in the two preceding regions; and, if some amongst them are also found in the temperate zones, a great many are peculiar to the equatorial seas.

These are general facts; and we may already draw from them this general inference, that each collection of species represents the mean temperature of the region it belongs to. But there are certain species more localised than others, and some more widely distributed. Thus the Búccinum undàtum, for example, is found from the North Cape to Senegal, modifying itself according to the temperature as it advances; so that it is easy to distinguish the varieties peculiar to the three or four principal conditions of climate. This species is not the only one thus extended; but at present I am acquainted with but a small number having, like this, the property of existing in temperatures so different.

Other species, more sensible, as it appears, to the influence of climate, are much more localised, and it is these which it is most important to know. I will specify some of them:

1. Búccinum glaciale. 2. Cárdium groenlandicum. These two species do not pass the polar circle, and are found in Norway and Greenland. 3. Terebrátula psittàcea. It inhabits between the 65th and 75th degree. In my opinion, these species, and some others, represent the mean temperature of the north of Norway.