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The accompanying sketch-section across the little River Scoot, was taken near Mr. Flint’s village. It may serve to convey an idea of the relative positions of the various beds which occur there. In this section, A represents the Gneissoid strata, with the band of crystalline limestone b; C denotes the Lower Silurian beds (limestone above, and, by inference, the reddish sand-rock below, as seen farther south); and D, denotes the Drift deposit.
Iu concluding this brief notice of the more salient geological features of Belleville and its vicinity, I am anxious to express my obligations to the family of Lewis Wallbridge, Esq., M.P. P., for mnch information respecting points of interest to be visited, and for the presentation of many fossils obtained in the neighbourhood.
Galbraith and Haughton's Scientific Manuals. Experimental and
Natural Science Series: Manual of the Animal Kingdom; Protozoa. By Professor J. Reay Greene.
This small volume has a double title; we have chosen that which presents it as the commencement of an extended series of manuals, because we thus give most information to our readers. Those who obtain it alone from curiosity respecting its particular subject, would make use of the other.
It is a beautifully printed, carefully illustrated, and neatly got up volume, containing only 88 pages, with a Bibliography of the subject, questions for examination, and an index ; to this are prefixed 30 pages of general introduction. Of course there is, within such limits, no attempt to characterise or enumerate genera and species. The object aimed at, is a general view of structure, arrangement and distribu
tion. In the case of the Protozoa, this may be all that most people need or could profit by, but as we rise in the animal kingdom, such a manual would appear very meagre.
We see announced as forthcoming, another Zoological volume from the pen of the author of that which lies before us, and a Botanical one from that of Professor Harvey of Dublin. We are curious to see whether the present manual is to be a model as to size, and if so, how the learned authors will acquit themselves in such trammels; but our present business is with Professor Greene's manual of the sub-kingdom, Protozoa. It must in the first place be conceded that in this department of zoology, accessible and trust-worthy information is greatly needed, and would be gladly received by a large class of readers. Professor Greene appears to be well acquainted with what has been written on the subject, and has laudably exerted himself, to give a clear, though much compressed account of what is known, in relation to these elementary forms of animal life. We are not satisfied with his mode of treating their classification. He regards them as being as yet too little understood for the limits of classes and orders to be well determined, and therefore only gives under the titles of the several groups which have been proposed, the subdivisions recommended by the authors who have chiefly studied them, accompanied by such structural and physiological particulars respecting at least some typical species as seem to be established by sufficient authority. For practical usefulness we should have preferred some attempt, even if confessedly only provisional, to harmonise what we seem to have learned from various investigators into a consistent system whose parts are brought into proper relation to each other and to the whole; and we confess we have no such ideas as to the necessary foundations and limits of what are entitled to be called classes and orders, as would deter us from applying these terms to the greater and secondary divisions, which, though liable to modification by increasing knowledge, seem now to express the relations of the creatures, which we agree with the author in regarding as a distinct, well established subkingdom of the animal kingdom. He indeed complains of the characters of PROTOZOA being almost wholly negative, but this may perhaps appear to be almost unavoidable in a lowest division of any large collection of objects. In the vegetable kingdom, the method we prefer, separates as a sub-kingdom, those plants which are without Vascular tissue—the mode of diposing that tissue when present,
giving characters to the remaining sub-kingdoms-and so in the animal kingdom, the development and disposition of the nervous system characterise the four higher divisions, whilst Protozoa are animals consisting of an animated jelly, (Sarcodium) with little differentiation of parts and no perceptible nervous system. We are aware indeed that there may possibly not be one of the sub-kingdoms, certainly none excepting the highest, in which there are not instances, where no nervous system can be demonstrated ; but in all such instances there is a manifest conformity to a type of structure, which directs our judgment as to the position of the object, whilst in Protozoa, wherever we have a tolerable acquaintance with the life history of the creature ve recognise not only the absence of the character. istics of another sub-kingdom, but the presence of certain features properly belonging to that we are considering. If we have materials in our hands which really justify us in establishing a sub-kingdom of Protozoa, they can hardly fail to suggest some opinion as to the mode of sub-dividing it. If groups of creatures have been examined and intelligibly described, the question of their relation to other knowu groups, and the comparative importance of their distinctive marks will arise, and should be solved to the best of our ability.
It seems to us, that the possession of a mouth, and consequently of an alimentary sac, with a somewhat definite figure, and an outer covering, differing in some degree from the mass of the body, characterise Infusoria (in the now received limited sense,) as the highest class of Protozoa. From them, Rhizopoda are distinguished, by having no difference, so far as is known, or only a slight difference in certain parts, in their external covering from the mass of their bodies, and by their power of protruding portions of their substance, in the form denominated Pseudopodia. Possibly the naked Rhizopoda, the Arcellina, the Foraminifera, and the Polycystina may be so many good orders in this class. Thalassicollida may be nearer akin to Sponges : of Gregarinida, nothing can as yet be satisfactorily decided, until a full history of at least some species, removes the doubts which at present are unavoidable respecting their nature.
Sponges for which we may adopt the name of Amorphozoa, form a third distinct class. Since no protrusion of pseudopodia is attributed to Thalassicollida and in some of them at least, cellæform bodies, seeming to contain germs are surrounded by spicules, not unlike the peculiar ovarian spicules of some sponges; we may perhaps regard
these organisms as one order of Amorphozoa. Without waiting for the expression of Dr. Bowerbank's views, we would not decide on the subdivision of the class, but would temporarily employ one of the existing arrangements to afford us that aid of system without which we can hardly proceed a step usefully in the study of nature. Whatever may be its defects, that founded on the nature of the skeleton, may serve the purpose, and at least exhibits remarkable analogies with the arrangement of Rhizopoda ; Thalassicollida representing naked Rhizopoda, the horny sponges having a certain correspondence with Arcellina--those with Silicious spicula being the analogues of Polycystina, and those with Calcareous spicula of Foraminifera. Did our space permit, we should endeavour to ascertain the proper arrangement of Infusoria also, being well convinced, that all other information is in a great degree thrown away, if not connected with an intelligible system, and that methods which are necessarily only provisional and in which we may be sensible of great defects, are yet far preferable to any attempts at communicating anatomical, physiological, or descriptive matter independently of systems, which never carry the student beyond insulated facts, and barren, because unconnected observations.
Although Professor Greene may not exactly see these things in the same light that we do, we are by no means insensible to the merits of his book. The Introduction is excellent and useful, and its extent can hardly deter the idlest reader. His accounts of the low, and generally minute organisms of which he treats are highly interesting, and cannot fail to diffuse information, and lead to the increase of knowledge, by enlisting a host of new inquirers. The proprietors of the series have done their part well, and their first number holds out a favourable promise for those which are to follow ; if what is more important is not sacrificed to over-anxiety after compression.
The Old Glaciers of Switzerland and North Wales. By A. C.
Ramsay, F.R.S. and G.S. London : Printed by Spottiswood and Co. 1859
Amongst the various records of a by-gone condition of things presented by Nature's archives to the interpretation of the geologist, few can compete in interest, and perhaps in difficulty of solution,
with those belonging to the great Drift or Glacial epoch: that period in the history of the earth's mutations, which immediately preceded, and gradually passaged into, the present or historic age. Broadly spread across the entire northern hemisphere, southward to a mean latitude (on this continent) of about 40° N., and again extending many degrees northwards from the southern pole, lie vast beds of clay, and sand, and gravel, mixed up with and overlaid by heaps of travelled stones or boulders; stones that have been brought by natural agencies, often across intervening seas and valleys, and over mountain ridges, miles and miles away from their original localities. Where hard and compact rocks lie underneath this boulder formation, or rise up amongst it, their surfaces are almost always found to be rounded, or smoothed and polished, and marked likewise in long and straight lines with narrow grooves and scratches. If these peculiarities be not always observable on exposed rock surfaces, their absence is chiefly due to the disintegrating action of the atmosphere, as they necessarily become obliterated, sooner or later, by the effects of weathering.
In Canada the drift formation is largely developed ; and in many places the underlying limestone and other rocks exhibit the polished surfaces and the long lines of grooving just alluded to. But it is in mountainous countries that the phenomena of the drift epoch are portrayed to us in their grandest outlines. There, in many localities within the limits of latitude already pointed out, the bill-sides present their rounded contours, smoothed, polished, and striated; the hill-tops bear their loads of boulder stones, balanced one upon another, or perched, perhaps, on isolated points of rock; and the valleys show their excavated hollows and lake-basins, their barriers of heaped up boulders, their bigh and furrowed walls, with other memorials of abrading agencies belonging, it may be there, to an older time, but which are still in action amongst the frozen solitudes of the remote north, and in the higher valleys of the Alps and other mountain chains. In these vaileys the broad ice-rivers still slowly push their way amidst the surrounding rocks, wearing and abrading them, and piling up at lower levels their stony burdens in the form of huge moraines.* This however leaves the tale balf told. To complete our view of the phenomena under which the drift accumulations took place, we must
In many glaciers the formation of a terminal moraine is prevented it should be observed by the action of the stream which results from the melting of the ice.