New Plants - Bamboo Incognito

Bamboo is a must-have for any Japanese garden.  Here is what I like about it:

• Upright and takes little floor space
• Beautiful foliage
• Dynamic - responds to movement of air
• Hopefully easy to grow and maintain.

On the left is the original plant I found through this free offer page.  I need help identifying this species.  It's a runner for sure.  On the right are the cuttings from the above plant planted on my balcony.

Here is another species, also unknown to me.  It grew in a nice grove. When I tried to dig out few plants I was struck how impenetrable the ground is.  It looked like there was nothing but layers of runners which my shovel failed to even dent.  After 1/2 an hour of cutting through runners I was able to extract a couple of inches of roots and two stalks.

Here are these in a container on my balcony.











Please help with IDing these!
Cheers!