A characteristic of this species which distinguishes it from others of the same genus is found in the number of its sporidia, spores as seen in the ascus or spore sack.
Sporidia of same inclosed in ascus with accompanying paraphyses.
Ascospore, hymenium or sporophore bearing anascus or asci.
In this species there are only two spores in each ascus or sac, and these are much larger than in the other species, which have eight spores in a sac or ascus.
As mentioned before, the connexion between these two groups is very doubtful, and the derivation of the ascus from an ordinary sporangium of the Zygomycetes cannot be accepted.
By this means the ascus cell is brought uppermost, and after the fusion of the two nuclei it develops enormously and produces the ascospores.
In the development of the ascus we find two nuclei at the base which fuse together to form the single nucleus of the young ascus.
It has lately been shown that there is a fusion of nuclei in connexion with ascus formation, so that there can be no doubt of the position of this extraordinary group of plants among the Ascomycetes.
According to his view, the ascus is in effect the sporangium with several spores, the conidium the sporangiole with but one spore, and that not loose but fused with the sporangiole wall.
This mode of spore-formation is totally different from that in the ascus; hence one of the difficulties of the acceptance of Brefeld's view of the homology of ascus and sporangium.
Miss Fraser in Humaria rutilans finds two reductions: a normal synaptic reduction in the first nuclear division of the ascus, and a peculiar reduction division termed brachymeiosis in the thirdascus division.
The ascus is thus one of the most sharply characterized structures among the fungi.
The yellow spores are very minute, each ascus containing eight of them, and they are divided by a transverse partition or septum.
The number of sporidia contained in an individual ascus is usually less than in the majority of the Ascomycetes, and the sporidia approximate more nearly to the globose form.
This operculum may be the more readily seen when the ascus is coloured by a drop of tincture of iodine.
The spores of the other species are eight in an ascus and are very much alike in size and shape, and do not furnish decided specific characters; but in this species their importance can not be overlooked.
In this species there are only two spores in each ascus or sack and these are much larger than the spores of the other species.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "ascus" in a variety of sentences. We hope that you will now be able to make sentences using this word.
