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Sometimes, however, the Chlamydomonas divides into eight parts, each of which is provided with four instead of two cilia. These "zoospores" conjugate in pairs, and give rise to quiescent bodies, which multiply by division, find eventually pass into the active state.
It would seem to be a reasonable inference, I think, based upon the theory above stated, that in this case the newly formed gonidium, unable to escape from its prison by reason of the abnormal strength of the cell wall, became after a while resolved into its component zoospores.
Sometimes biciliated minute cells are found; without any doubt they are zoospores derived from any algoid or fungoid species. I cannot say whether there exists any genetic connection between these various sorts of spores. It seems to me that probably numbers 1-4 represent resting states of the hyphomycetes.
Reproduced by division and by resting spores produced in sporangia formed after the conjugation of two cells and union of their contents, and by zoospores formed in the vegetative cells or in the germinating resting spores. Diatomaceae. Multiplied by division and by the formation of new larger individuals out of the contents of individual conjugated cells; perhaps also by spores and zoospores.
Others permanently formed of some multiple of four; the highest forms made up of compact, numerous, more or less closely joined cells. Reproduction: by cell division, by the conversion of the cell contents into zoospores, and by resting spores, formed sometimes after conjugation; in other cases, probably, by fecundation by spermatozoids. All the unicellular algae are included under this head.
Each cell of all the plants of this genus produces a large number of mobile cells zoospores. M. Berthelot, in the Journal de Pharmacie et de Chimie for March, states that from peculiar physical relations he is led to suspect that the true element carbon is unknown, and that diamond and graphite are substances of a different order.
Two separate portions of its protoplasm become fused together, surround themselves with a thick coat and give rise to a sort of vegetable egg called an oospore. After a period of rest, the contents of the oospore break up into a number of zoospores like those already described, each of which, after a period of activity, germinates in the ordinary way.
Reproduced by zoospores formed from the cell contents and breaking out from the surface, or by motionless spores formed from the whole contents. Palmellaceae.
There were also spores and mycelial filaments of fungi, dirt, and zoospores. The drops of dew were collected with capillary tubes such as were used in Edinburgh for vaccine virus. The fluid was then preserved and examined in the naval laboratory. In a few hours the spores disappeared. Observation 32.
If the whole history of the zoospores of Peronospora and of Coleochaete were unknown, they would undoubtedly be classed among "Monads" with the same right as Heteromita; why then may not Heteromita be a plant, even though the cycle of forms through which it passes shows no terms quite so complex as those which occur in Peronospora and Coleochaete?
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