Internet firms QXL.com and Lastminute.com and technology stalwart Amstrad have been expelled from the Techmark 100 index of London's top technology shares.

They remain parts of the Techmark All-share index, but a dramatic fall in their share prices triggered their demotion from the ranks of blue-chip technology companies. in London.

The online auctioneer, the shopping website and the electronics firm were joined by Horizon Technology, Eyretel, Lynx Group, Easynet, Dataflex Holdings and ITnet.

Newcomers in the Techmark are Autonomy, Galen Holdings, ARC International, TTP Communications, nCipher, Whatman, Phytopharm, Indigo Vision Group, Northgate Information and Solutions.

Techmark 100 membership is determined by market capitalisation, and the index lists so-called "high-growth" firms, companies that have - or had - the potential to bring their investors exceptional returns.

But there is an upper limit for technology firms. Anyone growing beyond a market value of �4bln will be taken out of the index - it would be simply too large for the other firms in the list that still have some growing to do.

High-growth firms in the index usually come from the internet, technology, media and telecommunications sector.

The Techmark share market was set up just one year ago, in an attempt to rival successful markets like Germany's Neuer Markt, France's Nouveau Marche and the giant of them all, the Nasdaq market in the United States.

The changes announced by the FTSE committee that compiles the index will become effective after the close of business on Friday.