Is a structure that contains spores and is located on the underside of fern leaves. basidium bacillus cilium sorus

Sorus is a structure that contains spores and is located on the underside of fern leaves. Sorus is a cluster of sporania. In fungi and lichens, the sorus is surrounded by an external layer. Sorus can be also called a fruit dot. 

Yes he thought they should be left to chance why, because he thought that was the best thing to do