From Inquiries into the Origin and Process of the Science of Heraldry in England by James Dallaway, p454
Left to right (click on the names of each for more examples):
The escallop, or scallop shell.
The fleur-de-lis, national symbol of France. There is some controversy over whether or not this is a stylized representation of a lily flower, with some writers contending that it is intended to be a spearhead, but most authorities agree with the former option.
The rose, possibly most famous for its historical significance in the English Wars of the Roses. It was, however, the badge of both houses (white for York; red for Lancaster), not a charge in their arms. Also, while roses can be seeded, slipped, and leaved proper, their main color must always be specified.
The cinquefoil. Originally, it was probably some sort of plant or flower with five leaves/petals, but it has become stylized into a conventional heraldic charge. Here it is shown pierced; that is not always the case.