437. Order Peronosporales (Peronosporineæ).—These include the downy mildews (Peronospora, Plasmopara, Phytopthora, etc.), and the white rust of crucifers and other plants (Cystopus = Albugo), [Chapter XIX].
2. SUBCLASS ZYGOMYCETES.
438. These are the conjugating fungi.
439. Order Mucorales (Mucorineæ).—This includes the black mold and its many relatives (Mucor, Rhizopus, etc.). [Chapter XIX].
440. Order Entomophthorales (Entomophthorineæ).—This order includes the “fly fungus” (Empusa) and its many relatives parasitic on insects. In the autumn and winter dead flies are often found stuck to window-panes, with a white ring of the conidia around each fly.
II. Class Ascomycetes. (The ascus series.)
1. SUBCLASS HEMIASCOMYCETES.
Fig. 251.
Dipodascus albidus. A, thread with sexual organs, ascogonium and antheridium; B, fertilized ascogonium developing ascus; C, ascus with spores; D, conidia. (After Lagerheim.)