The microscope : and its application to vegetable anatomy and physiology / by Dr. Hermann Schacht ; edited by Frederick Currey, M. A.

Hermann Schacht

Date:: 1855

Credit: The microscope : and its application to vegetable anatomy and physiology / by Dr. Hermann Schacht ; edited by Frederick Currey, M. A. Source: Wellcome Collection.

145/230 (page 121)

$will frequently be necessary to make longitudinal sections in different directions tlirougli the middle of the ovarv, and, if possible, also through the middle of the style, and through part of the stigma. It will more frequently happen that from the impossibility of making such longitiidinal sections the stigma and style must be examined se}>arately. In examining longi- tudinal sections of the ovary the attention must again be directed to the placentfe and o\’ules, to the position of the latter, to the connexion of the canal of the style Avith the hollow of the ovary, to the distribution of the vascular bundles which pass from the jAeduncle into the ovary, and to the subsequent ramifications of these bundles in the other ])arts of the flower. The most important part of the ovary is the ovule, the con- dition of which at the period of blossoming must be considered. Three tilings must be attended to in considering the OAuile. 1st. The existence and the number of the coats of the ovule ; 2ndly. The position of the OA'ule, and especially the situation of the micropyle with regard to the hilum; 3rdly. The situation of the embryo-sac, and its relation to the nucleus. These questions can seldom be solved by examining the whole OAUile; in the Orchideje, in Monotropa, and in certain species ol P^Tola, the ovules of which are very small and transjiai’ent, and whose delicate nature precludes the possibility of preparing them in any way, it is possible, by accurate adjustment, to examine the OAUiles entire. In most cases, however, thin lon- gitudinal sections must be made exactly through the middle of the ovule; in particular cases, such as in OEnothera, the best way of doing this is to make thin longitudinal sections through the ovary itself; amongst the many ovules which will be thiis cut through, some will be found here and there to liaA-e been accurately divided; these must be extracted under the simjjle microscope. In other plants, such as Iris and Cucurbita, a transA'erse section is more advantageous. In almost all other cases it will be necessary to detach the ovule itself, to place it upon the forefinger, and to make two cuts through it with a very sharp razor, so as to obtain a thin longitudiual lamella forming exactly the middle of the ovule. The best way of doing this is to slice off one side of the ovule, to turn the OA'ule round M$