In different parts of the coelenteron the endoderm may be of three principal types - (i) digestive endoderm, the primitive type, with cells of large size and considerably vacuolated, found in the hydranth; some of these cells may become special glandular cells, without flagella or contractile processes; (2) circulatory endoderm, without vacuoles and without basal contractile processes, found in the hydrorhiza and hydrocaulus; (3) supporting endoderm (fig.
The cytoplasm is largely concerned in the formation of spindle fibres and centrosomes, and such structures as the cell membrane, cilia, or flagella, the coenocentrum, nematoplasl~ or vibrioids and physodes are also products of its activity.
In some cases both the nucleus and the chromatophores may be carried along in the rotating stream, but in others, such as T.Titeila, the chloroplasts may remain motionless iii a non-motile layer of the cytoplasm in direct contact with the cell wall.i Desmids, Diatoms and Oscillaria show creeping movements probably due to the secretion of slime by the cells; the swarmspores and plasmodium of the Myxomycetes exhibit amoehoid movements; and the motile spores of Fungi and Algae, the spermatozoids of mosses, ferns, &c., move by means of delicate prolongations, cilia or flagella cf the protoplast.
At the an ~ ~ tenor end are attached - two cilia or flagella In, , C the Vascular Cryptogams -- ~ the structure is much the;il ~.: -; same, but a more or less ~ ~ ~ spherical mass of cyto 4 i~- - ~ plasm remains attached .8 ~ :~ to the posterior spirals, -.
TRYPANOSOMES, Or Haemoflagellates, minute Protozoan parasites, characterized by the possession of one or two flagella and an undulating membrane, and specially adapted for life in the blood of a vertebrate.'
In Trypanoplasma and Trypanophis there are two flagella, inserted into the body very close to the anterior end (fig.
Both flagella are inserted close together, near the anterior end of the body.
The larvae swim normally like the adult or suspend themselves by their flagella (not shown in the figures) vertically in mid-water.
About the eighth hour after commencement of development the membrane ruptures and the oval embryo escapes, swimming by means of its flagella at the surface of the sea for another twenty-four hours, during which the principal organs are laid down, although the mouth does not open until the close of this period.