 Predicates of kinds include those conveying properties of the kind as a whole, as in  (4a),  and those conveying properties characteristic of the instances of the kind, as in  (4b).  The kind-referential status of the bare nouns in  (4a, b)  is supported by the usual criteria for referentiality.  Pigeons will thus stand for a kind whose instances are particular pigeons, and water will stand for a kind (substance) whose instances are particular water quantities.