Experimental production of filaments and networks in cytoplasm of Cichorieae

1. 1. The cytoplasmic participate of epidermal cells of Lactuca saliva L. and of a number of plants belonging to the tribe Cichorieae consists of mitochondria, plastids and spherosomes. Their identification is effected on the hases of differential staining with Janus green B, different properties exhibited under the phase contrast microscope, and by experimental virescence of colorless plastids. 2. 2. When living epidermal cells of Cichorieae are mounted on a slide under anaerobic conditions for more than 3 hours, long filamentous structures appear in the cytoplasm. They branch, anastomose, form loops, networks, and change shape constantly. 3. 3. Spherical elements of the cytoplasm do not participate in the formation of branching filaments. 4. 4. Filaments and networks may also be produced in cells mounted under anaerobic conditions in liquid petrolatum and in olive oil. 5. 5. The filaments and networks are not dissolved in 30 per cent acetic acid. 6. 6. The heterogeneous filaments formed under anaerobic conditions are considered to be composed of modified plastids joined end-to-end and enveloped by a membrane which could be either an extension of the plastid membrane, or an interface membrane between the plastids and the cytoplasm.