Charles Thom

The Aspergillus Nidulans Group

SUMMARYThe Aspergillus nidulans group is divided into five species primarily upon the character of the ascospores produced. Differences in colony characters are also correlated with differences in ...

Conidium Production in Penicillium

The fertile hyphae or conidiophores may arise as branches from submerged or from aerial hyphae. They are septate except when they are very short. They have approximately the same diameter as the vegetative hyphae from which they branch. They are uniform in diameter from point of origin to the point where the conidium-producing complex of cells begins to form. The apex of the uppermost cell is frequently though not always swollen somewhat like the vesicle of Aspergillus, and the distal ends of branches if such are present are commonly also swollen, but the appearance of such swelling is not a uniform character within the species. The conidiophore proper should be measured from the point of origin to the base of the fruiting group of cells or branches. This part ceases to grow in length when fruiting commences, hence this measurement is more characteristic than a measurement including fruiting mass which frequently increases in length for several weeks by the production of new conidia.