Nepenthus,
the septemberflower is long stemmed, daisy like flower, normally arriving blue/purple; white with green centre, lilac, sometimes yellow.

As oppsed to santini chrysanths which are shorter stems but also can have similar daisy like flowers and coming in quite a few colors.
The difference would be in the petals. September is a more delicate looking petal whereas santini is like a minature reagan chrysanth.
But you probably know that already!