The elements of embryology. / By M. Foster ... and Francis M. Balfour.

  • Michael Foster
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: The elements of embryology. / By M. Foster ... and Francis M. Balfour. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    277/336 (page 251)
    APR] In any case the cutting-blade should for the first method of imbedding be kept freely wetted with spirit; and each section, as it is made, carefully floated on to a glass slide and then, the spirit having been removed,' mounted in glycerine, or treated with creosote or oil of cloves and turpentine a.nd mounted in balsam or dammar. It is well to guard the section with a small diaphragm of paper placed under the cover-slip. When the object has been imbedded in sper- maceti in the way recommended above, the, block of spermaceti and the razor should be moistened with olive oil and not with spirit. The sections must be floated from the razor on to the glass slip in the ordinary way and then treated with a mixture of turpentine (4 parts) and creosote (1 part) till all the oil and the spermaceti are removed. They may then be mounted in Canada balsam or dammar in the usual way. Even when the other methods of imbedding spoken of above are adopted, it will frequently be found advantageous to moisten the razor with creosote or oil of cloves rather than with spirit. Whichever method be followed, a series of sec- tions, each as thin as possible, should be obtained and carefully numbered, from head to tail or vice versa. They should at first at least all be retained for study, and not even the fragmentary ones thrown away, these being often the most instructive. The following transverse sections will perhaps be the most instructive. 1. Through the optic vesicles, shewing the optic stalks. 2. Through the hind-brain, shewing the auditory sacs. 3. Through the middle of the heart, shewing its rela- tions to the splanchnopleure and alimentary canal. 4. Through the point of divergence of the splanchno- pleure folds, shewing the venous roots of the heart. 5. Through the dorsal region, shewing the medullary