Published online by Cambridge University Press: 31 May 2012
Although additional papers of this series are in preparation, it is considered appropriate to publish the completed ones at this time and to present this interim, tabulated, summary of the preceding five papers to assist the reader in the recognition of the forms with which we have already dealt. Other forms occur on conifers in the mountainous regions of western Canada and the United States that are not well known taxonomically. When studies on them are completed, it is the intention to prepare a final summary of all work that has been done on this subject.