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OF

NATURAL HISTORY

FOR BEGINNERS

BEING DESCRIPTIONS OF A PROGRESSIVE
SERIES OF ZOOLOGICAL TYPES

BY

H. ALLEYNE NICHOLSON

M.D. D.Sc. M.A. PH. D. F.R.S.E. F.G.S. &c.

Professor of Natural History and Botany in University College, Toronto; formerly
Lecturer on Natural History in the Medical School of Edinburgh; &c.

WILLIAM BLACKWOOD AND SONS
EDINBURGH AND LONDON

MDCCCLXXIII

All Rights are reserved

NOVE

PRINTED BY WILLIAM BLACKWOOD AND SONS, EDINBURGH.

PREFACE.

It has recently been asserted that Zoology is not a subject which can profitably be taught in schools. In this opinion the author finds himself entirely unable to concur; and the present work is an attempt to solve, upon a new basis, the problem how the facts of Natural History can be imparted to the previously uninstructed beginner in such a manner that he may obtain some real knowledge of the subject, and not a mere parrot-like acquaintance with a greater or less number of technical

names.

In this work, no other preliminary knowledge is assumed in the learner than some slight acquaintance with the chief functions of the animal body. Or, it is assumed that the teacher, in the absence of such preliminary knowledge, will explain to the learner the meaning of such terms as "breathing-organs," "circulatory system," or the like, and will point out in what the processes of respiration and circulation really consist.

Instead of reviewing the divisions of the Animal Kingdom in a systematic manner, a series of common types has been chosen, representing the various classes of animals, and the leading peculiarities of these types have been described more or less fully. At the close of the description of each type, the characters which it possesses in common with the other members of its class are pointed out; and in a concluding chapter it, is shown how the classes may be arranged under larger divisions or "sub-kingdoms."

Two or three classes, as being of very small importance, have been altogether omitted. For obvious reasons, also, the reproductive system and processes of the ani

mals here described have been altogether ignored. For equally obvious reasons, the peculiarities which are connected with internal structures have been in many cases passed over in silence, or merely alluded to; whilst attention has been directed to the conspicuous characters which are afforded by external points of structure.

The animals selected as representatives of the various classes are, with few exceptions, common types; and any teacher may readily obtain all of them, or nearly allied forms, for class demonstration, so that all the more important points alluded to can be shown to the learner upon the specimens themselves.

The technical terms employed in the descriptions of the types are exceedingly few in number, and explanations of their meaning have been invariably inserted in the text, along with their derivation, thus rendering a separate glossary unnecessary.

With the exception of the forms here chosen as representatives of the classes of the Pteropoda and Brachiopoda, the author may be permitted to state that he has personally examined and dissected, either in the fresh. state or as preserved in alcohol, all the types here selected for description; and that in the cases excepted he has a similar personal acquaintance with forms closely allied to the ones described, whilst the latter have been studied by him as regards their hard parts. Since most of the forms here selected are of common occurrence, and since the author is by profession a teacher of Natural History, he does not state this as being in the smallest degree a fact worthy of praise, or, indeed, of mention at all in an ordinary way, but simply as a guarantee that he is not merely retailing second-hand information. Most of the facts, therefore, recounted in the present work, though by no means original, have been verified by the personal examination of the author; and the descriptions have been drawn from actual specimens.

UNIVERSITY COLLEGE, TORONTO,
June 2, 1873.

LIST OF ILLUSTRATIONS.

Page 7

1. Amaba developed in infusions: Amœba princeps,

2. Paramecium,

3. Hydra vulgaris, and diagram of the same,

4. Thread-cell of the Hydra,

5. Actinia mesembryanthemum, and diagram of the structure of the same,

6. Uraster rubens,

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7. Section of one of the arms of a Star-fish (Uraster rubens), 19 8. Eosphora aurita,

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9. Diagram of the anatomy of a Wheel-animalcule,

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10. The Medicinal Leech, its anterior sucker, and one of

the jaws,

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11. Diagrams of the Leech to show its internal structure, 12. The Common Lobster, viewed from below,

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13. Structure of the integumentary skeleton of the Lobster,
14. Diagram of the internal anatomy of the Lobster,
15. Tegenaria civilis,

16. Lithobius forficatus, and head of Lithobius Leachii,
17. Æshna grandis, and its metamorphoses,

18. Diagram of the anatomy of an insect,

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19. Flustra foliacea,

20. Diagram of the anatomy of Flustra,

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21. Phallusia mentula, and diagram of its structure,
22. Terebratula flavescens, its shell and internal anatomy,

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