Hmmm, they need some warmth but I'm not sure they like it hot. How hot are you talking? I don't know how long to tell you germination takes for those seeds, I haven't grown any of them. From a previous post or two of yours I see that you've germinated other sundews from seed...are these in the same conditions those were germinated in? Is the temperature warmer now, than it was for the others that germinated?
Did you receive these seeds in the same envelope with other seeds that you've successfully germinated? The reason I ask is that I got a packet of tracyii seeds that were guaranteed to be viable (paid bucks for them). I planted them identically to a filiformis variety...they sat side-by-side under the lights. The filiformis had an incredible germination rate but the tracyii pulled a big ZERO...nothing germinated. The guy was nice and refunded the money, but I lost that time and really wanted the seedlings. The only thing I can figure is *something* happened between California and Lower Alabama...they sat in a hot truck broke down for a day or two on I-10 west of Phoenix, in a hot mailbox when they were mailed, put in a microwave
, or something else happened. But, not nary a green speck came out of those seeds.
As for sealing in a plastic bag, I usually leave the bag cracked or a few holes poked in it to let a bit of fresh air pass in and out. Also, don't keep them in the sun or under lights that can heat them up too much...I usually will put them *beside* my grow lights...when I see a green speck I slide them on beneath the lights and open the bag/cover a bit more.