In Insects it is very notable. In some forcipated; to catch hold and tear their Prey[t]. In some aculeated, to pierce and wound Animals[], and suck their Blood. And in others strongly rigged with Jaws and Teeth, to gnaw and scrape out their Food, to carry Burdens[w] to perforate the Earth, yea the hardest Wood, yea even Stones themselves, for Houses[x] to themselves, and Nests for their young.
And lastly, in Birds it is no less remarkable. In the first Place, it is neatly shaped for piercing the Air, and making Way for the Body thro’ the airy Regions. In the next Place, it is hard and horny, which is a good Supplement for the want of Teeth, and causeth the Bill to have the Use and Service of the Hand. It’s hooked Form is of great Use to the rapacious Kind[y], in catching and holding their Prey, and in the Comminution thereof by tearing; to others it is no less serviceable to their Climbing, as well as neat and nice Comminution of their Food[z]. Its extraordinary Length and Slenderness is very useful to some, to search and grope for their Food in moorish Places[aa]; as its Length and Breadth is to others to hunt and search in muddy Places[bb]: And the contrary Form, namely, a thick, short, and sharp-edg’d Bill, is as useful to other Birds, who have occasion to husk and flay the Grains they swallow. But it would be endless, and tedious, to reckon up all the various Shapes, and commodious Mechanism of all; the Sharpness and Strength of those who have Occasion to perforate Wood and Shells[cc]; the Slenderness and Neatness of such as pick up small Insects; the Cross-form of such as break up Fruits[dd]; the compressed Form of others[ee], with many other curious and artificial Forms, all suited to the Way of Living, and peculiar Occasions of the several Species of Birds. Thus much for the Mouth.
Let us next take a short View of the Teeth[ff], In which their peculiar Hardness[gg] is remarkable, their Growth[hh] also, their firm Insertion and Bandage in the Gums and Jaws, and their various Shape and Strength, suited to their various Occasion and Use[ii]; the foremost weak and farthest from the Center, as being only Preparers to the rest; the others being to grind and mince, are accordingly made stronger, and placed nearer the Center of Motion and Strength. Likewise their various Form[kk], in various Animals is considerable, being all curiously adapted to the peculiar Food[ll], and Occasions of the several Species of Animals[mm]. And lastly, the temporary Defect of them[nn], is no less observable in Children, and such young Creatures, where there is no Occasion for them; but they would be rather an Annoyance to the tender Nipples and Breasts.
From the Teeth, the grand Instruments of Mastication; let us proceed to the other ministerial Parts. And here the Parotid, Sublingual, and maxillary Glands; together with those of the Cheeks and Lips, are considerable; all lodged in the most convenient Places about the Mouth and Throat to afford that noble digestive salival Liquor, to be mixed with the Food in Mastication, and to moisten and lubricate the Passages, to give an easie descent to the Food. The commodious Form also of the Jaws, deserves our Notice; together with the strong Articulation of the lowermost, and its Motion. And lastly, the curious Form, the great Strength, the convenient Lodgment and Situation of the several Muscles and Tendons[oo], all ministring to this so necessary an Act of Life, as Mastication is; they are such Contrivances, such Works, as plainly set forth the infinite Workman’s Care and Skill.
Next to the Mouth, the Gullet presenteth it self; in every Creature well-siz’d to the Food it hath occasion to swallow; in some but narrow, in others as large and extensive[pp]; in all exceedingly remarkable for the curious Mechanism of its Muscles, and the artificial Decussation and Position of their Fibres[qq].
And now we are arriv’d to the grand Receptacle of the Food, the Stomach; for the most Part as various as the Food to be convey’d therein. And here I might describe the admirable Mechanism of its Tunicks, Muscles, Glands, the Nerves, Arteries and Veins[rr]; all manifesting the super-eminent Contrivance and Art of the infinite Workman[ss]; they being all nicely adjusted to their respective Place, Occasion and Service. I might also insist upon that most necessary Office of Digestion; and here consider that wonderful Faculty of the Stomachs of all Creatures, to dissolve[tt] all the several Sorts of Food appropriated to their Species; even sometimes Things of that Consistency as seem insoluble[uu]; especially by such seemingly simple and weak Menstruums as we find in their Stomachs: But I shall only give these Things a bare mention, and take more peculiar Notice of the Special Provision made in the particular Species of Animals, for the Digestion of that special Food appointed them.
And in the first Place it is observable, that, in every Species of Animals, the Strength and Size of their Stomach[ww] is conformable to their Food. Such whose Food is more delicate, tender, and nutritive, have commonly this Part thinner, weaker, and less bulky; whereas such whose Aliment is less nutritive, or whose Bodies require larger Supplies to answer their Bulk, their Labours, and waste of Strength and Spirits, in them it is large and strong.
Another very remarkable Thing in this Part, is, the Number of Ventricles in divers Creatures. In many but one; in some two or more[xx]. In such as make a sufficient Comminution of the Food in the Mouth, one suffices. But where Teeth are wanting, and the Food dry and hard, (as in granivorous Birds,) there the Defect is abundantly supply’d by one thin membranaceous Ventricle, to receive and moisten the Food, and another thick, strong, muscular one, to grind and tear[yy] it. But in such Birds, and other Creatures, whose Food is not Grain, but Flesh, Fruits, Insects, or partly one, partly the other, there their Stomachs are accordingly conformable to their Food[zz], stronger or weaker, membranaceous or muscular.
But as remarkable a Thing, as any in this Part of Animals, is, the curious Contrivance and Fabrick of the several Ventricles of ruminating Creatures. The very Act it self of Rumination, is an excellent Provision for the compleat Mastication of the Food, at the Resting, leisure Times of the Animal. But the Apparatus for this Service, of divers Ventricles for its various Uses and Purposes, together with their curious Mechanism, deserves great Admiration[aaa].