Forms, and Triangles

"Whatever is given us as object must be given us in intuition. All our intuition, however, takes place by means of the senses only; the understanding intuits nothing but only reflects. And as we have just shown that the senses never and in no manner enable us to know things in themselves, but only their appearances, which are mere representations of the sensibility, we conclude that 'all bodies, together with the space in which they are, must be considered nothing but mere representations in us, and exist nowhere but in our thoughts.' " (Remark II [p36])

I'm not sure if this is in response to Peter's post, or more of a continuation, but I too was stuck on Descartes', I mean Kant's description of space. Here Kant says "all bodies, together in the space in which they are, must be considered nothing but mere representations in us, and exist nowhere but in our thoughts." If I am reading this right, then (in response to Peter) space (and therefore time as well?) is not necessary, but is instead simply our understanding of the form.(?) If I am not reading correctly, then I am pretty confused and either muddling or continuing Peter's question.

I also hope someone can help me understand the triangles in hemispheres part, whether in class or via the blog. I was having trouble visualizing it. (§13 285-286 [p33])