Irish Naturalist Volume 8 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1899 Excerpt: ...brain and the dentition of a horse. The advantages of a study of the latter will appear when it is remembered that horse-breeding is much favoured in Ireland, and the difficulties of telling the age (say between four years and five years) are very great indeed. Blaschka's models of various invertebrate types, Fritch's elegant dissections, and some special casts of viscera serve to illustrate forms that are not always available in a fresh condition. The collection of dried plants and fruits is of the ordinary kind. The apparatus for illustration include a series of panoramic diagrams on rollers, that enable the student to see the figures in a progressive series, and save much trouble to assistants in arranging drawings for demonstration. An apparatus for determining the rotation of limbs consists of a frame with a graduated circle, by which the amount of rotation and its character can be understood. A vertical shaft that carries framed diagrams is a useful apparatus; the latter is in use elsewhere, especially in picture galleries. A microscope with a revolving platform is one of the most satisfactory instruments. Specimens can be examined in succession by turning a handle. The instrument is enclosed in a box so that it cannot be injured in any way by a visitor or an observer. One case is of very great interest--the case of disarticulated skulls. These are of great value in the study of the size and distribution of the bone bars and plates in the skulls of different groups; such skulls can be advantageously compared with those that are intact or with special sections. Stopping for a moment to mention the groups of birds' nests and eggs, a combination may be mentioned that partakes partly of the nature of a laboratory, a biological cabinet, and a museum, viz., ...