Sometimes the spore wall has several layers. Of these the endosporium is the innermost, and is usually quite thin. Sometimes the developing spore is enveloped by a membrane called a perisporium, which usually sloughs off as the spore matures.
R. Heim, in his (1931) Le genre Inocybe proposed that this should be called the peripheral envelope instead – when talking about Inocybes. The episporium is considered the fundamental layer of the spore wall; it is the thickest, gives rise to whatever ornamentation there is, and is also responsible for the spore’s color. The mesosporium sometimes occurs, in between the episporium and the endosporium; and the exosporium sometimes covers the episporium (and is pierced by its ornamentation) but is in turn covered by the perisporium.
Created: 2019-07-06 19:06:01 CEST (+0200)
Last modified: 2019-07-06 19:06:01 CEST (+0200)