Natura - nature actualia - actual entities Mundus Plinius - physical world particles hadrons - composite particles mesons - bosonic hadrons b bbar mesons 01 Upsilon(1S) 02 chi(b0)(1P) 03 chi(b1)(1P) 04 chi(b2)(1P) 05 Upsilon(2S) 06 chi(b0)(2P) 07 chi(b1)(2P) 08 chi(b2)(2P) 09 Upsilon(3S) 10 Upsilon(4S) 11 Upsilon(10860) 12 Upsilon(11020)