...
 class Allosaurus : Dinosaur {
   public Allosaurus (string theName, int length){
      this.Name = theName;
      this.Length = length;
   }
 }
 class TRex : Dinosaur {
   public TRex (string theName, int length){
      this.Name = theName;
      this.Length = length;
   }
 }

...