I work as a GP and a patient who is a gardener brought this spider into surgery today having been bitten on his forearm when it fell out of some brambles he was clearing (in a large garden in the middle of Bristol). It was a sting like bite and he developd a weald the size of a 5p piece after a few minutes. He also experienced some tingling in the skin around the bite. This gardener comes from Australia and so was understandably anxious about the possibility of a venomous spider bite. I was able to reassure him that there was no chance of a seriously toxic reaction to any British spider but we would both be curious to know what this species is. I think it was female because it deposited some white eggs in the web it wove while in the temporary container. It has very black legs and upper body but a velvety brown abdomen with no other markings. It also has very large mouth parts! Apologies for the fuzzy photo:
Looks like a 'Tube Web' to me as well. Been researching 'em today, as my niece was bitten yesterday (two obvious puncture wounds and pain subsided after a few hours) and her photograph (very blurry) looked unlike anything I had seen before.