Sentence:  The Erysiphacae may possibly have given rise to the Laboulbeniales, the only other group in which a single daughter cell of the oogonium is responsible for the asci, and perhaps to the lower Pyrenomycetes also; these, like the Erysiphaceae, have regularly arranged asci, and in "Chaetomium fimete" the perithecium is without an <WSD>ostiole</WSD>. 
Meaning of the word marked with <WSD> tags:  A small hole or opening through which certain fungi release their mature spores.