EXHIBIT 8.1 Subsidiary undertakings held directly Jurisdiction of % holding - ------------------------------------- incorporation (all classes ------------- of shares) ---------- CeNeS Drug Delivery Limited Scotland 100% CeNeS Pharmaceutical Limited Scotland 100% CeNeS Limited England 100% England CeNeS Contract Research Limited 100% CeNeS Pharmaceuticals, Inc. (formerly Cambridge NeuroScience, Inc.) Delaware 100% CeNeS (Bermuda) Limited Bermuda 80.1% Cambridge Cognition Limited England 86.9% Cambridge Cognition Guarantee Limited England 100% Subsidiary undertakings held indirectly Cambridge Management Dynamics Limited England 100% CeNeS Research Limited (formerly Cambridge Cognition England 100% Limited) 1