Making three groups of the primates, you'd do better to refer to prosimians, rather than lemurs. Prosimians include various lemurs, dwarf lemurs, cifaks, pottos, aye-ayes, bush babys, tarsiers, lorises, and probably a few other families I'm forgetting. Some of these have tails, some of them don't.

In case you're wondering, I know such things because I had a girlfriend once who was really into prosimians. And actually, they are pretty cool.