The accurate drawing of the vinegar eels made by Mr. C. Whitley for this paper, so faithfully portrays the little creature in its several phases of life, that it appears unnecessary to add anything by way of further description. It may, however, not be uninteresting to add, that this minute and curious eel is not unfrequently made the means of practising upon the unwary a gross but very characteristic imposition by the advertising quacks who infest this great metropolis. A victim offering himself to be fleeced is usually received in a well made-up room, lined by book-cases and illuminated diagrams of the organic structures in the human body, healthy and unhealthy. Instead of the old-fashioned stuffed alligators suspended from the ceiling, the Paracelsus of modern times ostentatiously parades the most showy and expensive microscope obtainable, in closest consultation with which he takes care to be found by the patient, just as an ant-lion may be supposed to be studying nature as he reposes at the bottom of his conical trap, the sloping sides of which, made up of the finest sand, prove a very facilis descensus to his unsuspecting prey, who ventures on the treacherous surface. Proceeding to business after some preliminary anxious inquiries, the doctor (!) gravely proposes to aid his diagnosis by that crucial test, the microscope. The dismay of the poor victim may be more easily imagined than described, when, on being pressed to see for himself, the state of affairs is revealed to his agitated mind, in a mass of wriggling little worms, disporting themselves in the smallest drop of fluid derived from his natural juices. The doom of Herod-" and he was eaten of worms "to him needs no more elucidating commentary, and if the conscience-smitten patient does not, like the tetrarch, presently give up the ghost, he is in a very apt mood to part with all the cash he may have about him, in order to be kept out of a situation, the horrible nature of which, had it not thus been demonstrated to his senses, he could never have conceived. I have sketched no overdrawn picture, but rather one, I fear, of daily occurrence; and the manner all this is effected is exceedingly simple. The smallest particle of sour paste, previously placed on a slip of glass, lies imperceptible to the unpractised

never meant to infer that the vinegar itself contains no organic matter. But there is no need to discuss the question of heterogenesis with reference to vinegar; for boiled distilled water alone will, if exposed for a few days (under certain conditions of the atmosphere), be found to contain distinct types of Infusoria. This fact we discovered last summer, and communicated to Section D of the British Association. So our scientific readers must not suppose that we have been seeking to adduce evidence in favour of the theory of spontaneous generation.-ED.

eye, until a single drop of any fluid secretion from the body supplies the required conditions of moisture; and, accordingly, the little paste-eels are immediately aroused to life and activity, reversing the fable of the frogs and boys, as the lively enjoyment they exhibit is apt to prove a very serious matter to the human being so shamefully victimized.

EXPLANATION OF PLATE X.

Figs. 1 & 2. Young animals soon after leaving the egg.

Fig. 3. Male, full grown.

Fig. 4. Male, with reproductive organs in situ, separated at c and d, and magnified × 350.

Figs. 5 & 6. Females, with ovisacs in situ, containing eggs in various stages of development.

a a. Eggs thrown off and found floating in the fluid.

Fig. 7. A dead male, in which state they float about for days, until destroyed by vibriones.

THE EYE OF THE OX.

BY E. BECKIT TRUMAN.

HOMER, the sublimest, because the most natural, of the classic poets, expresses his idea of the majesty and beauty of the countenance of Juno, by the epithet boōpis, ox-eyed. The simile may, perhaps, appear a very humble one; but, by a little study of the formation of the bullock's eye, we may see that not only is the object worthy of the Homeric application, but that it contains numberless beauties of which the ancient Grecian never dreamed, disclosed to us by the aid of the dissecting-knife and the microscope.

The delicacy of the internal organization of the eye requires it to have an abode where it will be protected from external violence. Such a dwelling-place we find in the orbit or socket of the eye which is formed of bone on all sides, and lined by a cushion of fat, in which the eyeball is embedded; so that in the event of a blow being received on the only attainable aspect, the front of the eye, its force is transmitted to, and broken by, this soft layer of fat, and thereby prevented from rebounding injuriously on the eye from the unyielding wall surrounding it.

Having removed the eyeball from its socket, and divested it of the fat and the muscles, let us examine the contour of the eye (Plate XI., fig. 1). We see it to consist of two portions, of differing curvatures, the part in front (a) having the greater convexity; the remaining and greater portion having the form of a somewhat-flattened globe. The projecting body (f) is the optic nerve, the nerve that conveys the visual impressions to the brain; at c and d are the attachments of muscles cut short; and at e some blood-vessels are seen.

We will now examine, one by one, the different structures of which the eyeball is composed; and which consist (1) of tunics or protective coverings, (2) of a series of refracting bodies to bring the rays of light to a focus internally, and (3) a nerve to receive the impression of light (with certain auxiliaries). The outermost covering of the eye consists of two very dissimilar parts; namely, the cornea and the sclerotic. The cornea,