It is a fungus or mold common in the enviroment. Species are common contaminents of starchy foods such as bread and potatoes. It also grows in many plants and trees. Some species can cause infections of the ear, skin lesions and ulcer in human.
Aspergillus (I presume that this is what you mean) is a fungus which can infect people with compromised immune systems, generally in the lungs, but also elsewhere.
Aperillis is a mold that is naturally occuring in nature. It is one of the most common types of mold, and can cause infections in both people and animals. Most of the mold that grows on food is this type of mold.
A very rapid method for this and for similar small filamentous forms may be added. Forms as large as Thamnidium elegans can be mounted successfully by this method.