Comparing my own observations on this low type with the results given of the study of the chick in Foster and Balfour's excellent work, I find that few paragraphs in it would need any material alteration, and that the figures would mostly serve very accurately if in that work the word chick were to be exchanged for that of snake embryo.

The development of the vesicles of the brain, the organs of special sense, the rudiments of the cranium and face-those things that come across my path, to say nothing of the rest of the growing germ, all are developed similarly in the snake, below, and in the bird, above.

Like all the Vertebrata above the fishes and amphibia ("Ichthyopsida "), the embryo of the snake has the folds and clefts behind the mouth few and small; yet there is no change of pattern, and the rudiments of three pairs of gill-arches with their clefts can be made out.

But no embryo I have studied shows more clearly that all the folds that lie about the mouth, before and behind, as well as those that form the mouth itself, belong to one category.

Whilst the brain is merely a row of three vesicles, and the rudiments of the sense-capsules are three folds, or unclosed vesicles, the sides of the head grow downwards as a series of folds parted by deep notches or clefts.

These clefts are the "naso-lacrymal" in front of the rudimentary mouth; the mouth-clefts (right and left); the "tympano-eustachian ;" and the three "hyo-branchial" clefts behind that.

The first folds lie under the fore-brain; these are the "fronto-nasal processes or flaps; the second are the "maxillo-palatine; " the third, the mandibular; the fourth, the hyoid; and the fifth, sixth, and seventh are rudimentary branchials, that never give off branchial filaments or plicæ.

The cavity of the mouth is formed by the absorption of the mesoblast that lay in the angle of the head-bent double upon itself-just below the end of the notochord.

The walls of the mouth are formed by the maxillo-palatine rudiments in front, and the mandibular rudiments behind; below, the floor of the face is suppressed; at the sides, the right and left cleft form the right and left angle of the mouth.

The visceral folds develop but little cartilage; an outgrowth from the anterior ends of the trabeculæ grows downwards and backwards into the fronto-nasal process. It represents two visceral rudiments, the axis of the pre-maxillary arch; but this flap is single.

The maxillopalatine folds develop no cartilage, but become rich in "parosteal" bones.

Each mandible develops a large quadrate and a long articulomeckelian cartilage.

All the cartilage seen on each side behind the lower jaw is a small

"epi-hyal" ("hyo-mandibular "), which becomes the stem of the "columella auris;" but the "branchial" folds develop no cartilage in them, and soon are lost in the sides of the neck.

The ear

There is but little cartilage developed in the cranium. capsules are large, long, and become solid cartilage before they ossify, and the simple nasal roofs chondrify and never ossify.

There is a large cartilaginous occipital ring or arch, but the sphenoidal regions, which have exceptionally autogenous alæ, are very feeble and small.

The trabeculæ, which are manifestly mere outgrowths of the parachoidal tracts, develop into long terete rods of cartilage, but do not ossify at all in front of the pituitary space.

They coalesce in the internasal region, and coalescing also with the descending lamina of each nasal roof-cartilage, they form a low septum. nasi.

There are two pairs of " extra-visceral," or labial, cartilages.

The "epi-hyal" rudiment coalesces during chondrification with the stapedial plate; it gives off a small scale from its postero-superior edge. This is a minute rudiment of the "stylo-hyal" element.

Both in the cranium and face there is a copious growth of very perfect bone developed in the sub-cutaneous stroma. In the cranium the frontals quite, and the parietals almost, meet below. Thus the trabeculæ are excluded from taking part in the formation of the front part of the cranial cavity.

These rods lie in the grooved sides of the "parasphenoid," which has no basi-temporal part, as in the bird, but becomes ankylosed to the double, ectosteal basi-sphenoid.

These are some of the most striking points in the growing snake's skull; for the rest I must refer to the main paper. I may, however, make a few remarks upon 66 the new things" to be seen in this low sauropsidan skull.

The occipital condyles are confluent at the mid-line, so as to form a rounded single surface, with a dimpled middle part.

The auditory capsule acquires three bony centres that do not unite with each other, but with the nearest bones of the cranium.

Thus the prootic coalesces with the alisphenoid, the epiotic with the superoccipital, and the opisthotic with the exoccipital.

The columella and stapes are one bone, not distinct as in the batrachia. The union takes place very early.

The mandible opens very far back, behind the occiput, and as the quadrate passes over the stylo-hyal, the two become ankylosed together. For the palate a new bone appears, namely the "trans-palatine;" but the meso-pterygoid is not distinct from the pterygoid in the ophidia. It occurs in Anguis fragilis.

The little "pre-orbitals" that in the Amphibia form a floor to the

narial passage, and are termed by me the "septo-maxillaries," attain their highest development in serpents and lizards. I do not find them in the tortoises and crocodiles, but they re-appear-very small-in carinate birds, in connection, as in the snakes, with the vomers and labial cartilages.

In the mandible the upper part of Meckel's cartilage ossifies as the "articulare," and now we get the full number of the splints, namely, five-the dentary, sphenial, coronoid, angular, and surangular. The pier is a single bone, the quadrate. These six pairs of bones forming the free mandible occur also in the lizards, crocodiles, and in most birds In tortoises they are fewer, and in gallinaceous birds I have failed to find the coronoid piece at any stage.

The tongue of the snake shows no cartilage in its structure; neither cerato-hyal, basi-hyal, or thyro-hyal, have appeared in any of my dissections.

IV. "Observations on the Nervous System of Aurelia aurita." By EDWARD ALBERT SCHÄFER, Assistant Professor of Physiology in University College, London. Communicated by W. SHARPEY, M.D., LL.D., F.R.S. Received October 31, 1877.

(Abstract.)

The author describes the nervous system of Aurelia as consisting, in addition to the lithocysts and certain tracts of specially modified epithelium in their neighbourhood, of an interlacement of nerve-fibres covering the whole of the under surface of the umbrella and lying between the ectodermal epithelium and the muscular sheet. Each nerve-fibre presents near the middle of its course a nucleated enlargement in the shape of a bipolar nerve-cell, which is thus interpolated in the course of the fibre. With regard to these nerve-fibres it is remarked-firstly, that they are of limited length, seldom exceeding four millimetres; secondly, that they never come into actual continuity with other fibres, although they frequently run closely parallel for a certain distance, and often form extremely intricate interlacements by the coming together of a number of fibres. The fibres occasionally branch. They are described as ending generally by finely-tapered extremities, which are in close contact with the substance of the muscular fibres, but sometimes the termination of the nerve is dilated into a flattened nucleated expansion, probably a primitive form of motorial end plate.

The structure and relations of the lithocysts are then treated of. The lithocyst is described as consisting of an ectodermic covering and an endodermic core, the two being nearly everywhere separated by a

thin layer of the jelly-like mesoderm. The ectodermic covering consists, except over the free end where the cells are simple and flattened, of long columnar, ciliated cells, the fixed ends branching into delicate fibres, which form a stratum underneath the epithelium. A similar condition of the ectoderm is described as met with in two depressions of the surface, one being situate above, and the other below, the lithocyst; and the resemblance which the elongated epithelium cells with the subjacent granular-looking, but in reality fibrous stratum, exhibits to the developing central nervous structures in the vertebrate embryo is pointed out. These parts, in fact, probably represent the first beginnings phylogenetically-of a central nervous system. Some of the cells of the ectodermic covering of the lithocyst are pigmented, and these cells are provided each with an excessively long and fine (sensorial) filament instead of with vibratile cilia.

The endodermic core of the lithocyst consists of a prolongation from the nutritive canal of the margin, which at the terminal part of the lithocyst is continued as a solid projection, the cells of which contain calcareous crystals or otoliths.

A small lithocyst is further described, in which the otolithic prolongation of the nutritive canal penetrated the ectodermic covering, and projected freely into the surrounding medium.

Reference is made to the observations of Haeckel upon the nervous system of Geryonia and Cunina, and to a recently published preliminary notice by Oscar and Richard Hertwig, of the structure of the nervetracts and sense-organs in various other genera of Medusæ.

January 17, 1878.

Sir JOSEPH HOOKER, K.C.S.I., President, in the Chair. The Presents received were laid on the table, and thanks ordered for them.

The following Papers were read:

I. "On Cobra Poison." By ALEXANDER PEDLER, F.C.S., Professor of Chemistry in the Presidency College, Calcutta. Communicated by Dr. FRANKLAND, F.R.S., Professor of Chemistry in the Royal School of Mines. Received November 1, 1877.

On my arrival in India my attention was strongly directed to the enormous number of deaths, annually resulting from the bites of poisonous snakes. Statistics of the deaths from such causes are

VOL. XXVII.

C

collected by the various Provincial Governments of India, but as might be expected the difficulty of obtaining correct returns is very great, and it is certain that the number registered is far short of the real mortality resulting from this cause. Even with such incorrect returns, however, as many as 11,416 deaths in India from the bites of poisonous snakes were reported during a single year,* and it is probably within the mark to say that in the whole of India the annual number of deaths from snake bite is not less than 15,000.

Experiments without number have been made with a view to discover an antidote for snake virus; but although many so-called remedies have been reported, it has been found on closer examination, that none of them have been of the slightest efficacy either in modifying the action of the poison, or in any way tending to save life. The nearest approach to success among these unsuccessful remedies appears to have been the system of artificial respiration, suggested by Sir J. Fayrer, and extensively experimented with by the Snake Poison Commission at Calcutta, whose report was published in 1874,† and who found that, although life might be prolonged by the use of artificial respiration after poisoning by snake virus, in no case was there any ultimate hope of saving life by this means.

So far as I am acquainted with their results, the researches of other chemists have been hitherto unsuccessful either in elucidating the nature of the poison, or in ascribing any composition to the active principle which must be present. This want of success is the only justification of my bringing the result of my own researches before the Royal Society at all; while the great practical importance of a satisfactory solution of the problem will, I hope, be accepted as my apology for laying my work before them in its present incomplete form.

Of all the snakes in India the cobra (Naja tripudians) is the cause of the largest number of deaths, and the experiments here described were all made with cobra poison, extracted from the snakes in my own presence, by the usual method as described in published memoirs on the subject of snake poisoning. As may be imagined, the supply of cobra poison which is obtainable is very small, each snake yielding only from one to three grains of solid poison; so that, in all my experiments, I have been continually hampered with the extreme difficulty of procuring a sufficient amount of the poison to work with on a satisfactory scale. In submitting my results to the Society, I must at the outset state that it is possible that after further experiments I may have to modify some of the results here given.

The liquid poison, which, when extracted from the cobra, has a slightly alkaline reaction, was found to have a specific gravity of 1.095

* 1869. See Fayrer, Proc. Roy. Soc., xxi, p. 360.

+ Report on Indian and Australian Snake Poisoning. Bengal Secretariat Press, Calcutta.