Jen,

I think you're dead on with your genus IDs, but I am sorry, I can't help you with the specifics.....

Yep I think you're right too, some close-ups of each plant might help get species ID.

CP

Notocactus schlosseri - sure!

And your Gymno is looking like a damsii...maybe?

Hi Rob & Scott,

I looked up that Noto and you're dead on w/that one. Thanks so much! I just love those orange spines. Scott, could very well be G. Damsii, you said in another post yours gets white flowers? Mine are light pink. Mine has some purple on the body. I've been looking at pics and it does look a lot like many of them. Thank you guys for your help.

Jen

The Mammillaria that you have there, could be M. perbella or pseudoperbella
Alfonso