zygospore's Usage Examples:

Different stages in the formation and germination of the zygospore.

Some Zygnemaceae and Mesocarpaceae form either a short conjugating tube, or none at all, but the filaments approach each other by a knee-like bend, and the zygospore is formed at the point of contact, often being partially contained within the walls of the parent-cell.

The germination of a zygospore or oospore is effected by the rupture of an outer cuticularized exosporium; then the cell may protrude an inner wall, the endosporium, and grow out into the new plant (Vaucheria), or the contents may break up into a first brood of zoospores.

Mycelium well developed; sexual reproduction by zygospores; asexual reproduction by sporangia and conidia.

The majority of forms, however, fall into the heterothallic group, in which the association of branches from two mycelia different in I nature is necessary for the 2, formation of zygospores.

In Sporodinia the branches give rise also to short branches, which meet and fuse their contents to form zygospores.

In the first group zygospores can arise by the union of branches from the same mycelium and so can be produced by the growth from a single spore; this group includes Spordinia grandis, Spinellus fusiger, some species of Mucor, 'c.

The classification of the Mucorini depends on the prevalence and characters of the conidia, and of the sporangia and zygospores - e.

Gametes which fail to conjugate sometimes assume the appearance of zygospores and germinate in due course.

In Zygnemaceae there is no dissolution of the filaments, but the whole contents of one cell pass over by means of a conjugation-tube into the cavity of a cell of a neighbouring filament, where the zygospore is formed by the fusion of the two FIG.