Senecio stapeliformis. Unusual plant, not the kind that should ever be grown in glass.

I think it is senecio stapeliiformis.I don't know anything about it though.I advise you to plant the others much higher,they should be over the rim.

No succulent should be potted in a container without drainage hole(s). Layering different substrates doesn't solve the potential problem. Ingredients making well draining mix should be of approx. same size, and mixed thoroughly. And your plants are potted way too deep inside of container - creating poor air flow and slightly increasing humidity. On top of that, light on the substrate (thru the glass) will encourage growth of algae. It isn't going to kill your plants, but is unsightly.