Page:Walcott Cambrian Geology and Paleontology II.djvu/333



.—The first reference to each of the species described gives the page upon which the description begins and the figure references. References to the description of certain parts or features of a species are as a rule only given in the index if the description occurs outside of the detailed description of the species. For instance: the description of the pygidium of a certain species will be found in the description of that species and there will be no specific reference in the index to the pygidium unless it is described or discussed at some other point in the paper.

The references in heavy-faced type refer to the pages upon which the species are described.