Abstract: A photographing apparatus for microscopes, in order to make it possible to obtain a photograph of a proper exposure always irrespective of the size of a sample image, comprising an indicator arranged in a position substantially conjugate with an image surface of the photographing apparatus, a first light source for illuminating the indicator, an output generating means for determining an exposure time in photographing of a sample image and an adjusting means capable of proportionally adjusting the brightness of the first light source and an output to be issued from the output generating means, an output to be issued from the output generating means being determined so as to make it possible to photograph the sample image with a proper exposure by operating the first adjusting means to make the brightness of the indicator coincide with the brightness of the sample image formed on the indicator.

Abstract: Biological substances such as tissues, cells, vaccines and viruses are cultured by the steps of: introducing a culture solution having the substances suspended therein into a closed culture vessel having a plurality of disc-like implantation plates arranged horizontally with a certain space between successive plates so that a predetermined number of the implantation plates is immersed in the culture solution; culturing the substances on the surface of the implantation plates; removing the substances from the implantation plates; suspending the removed cultured substances in a new culture solution; and successively repeating the steps of culturing, removing the cultured substances and suspending in a new culture solution while each time increasing the amount of newly supplied culture solution to progressively increase the number of implantation plates immersed in the culture solution.