Dr. Masters read before the Royal Horticultural Society the substance of a letter from Dr. Engelmann, relating to these plants, in which the historian of the American Conifers stated, that he had now seen the species concolor extensively distributed in a living state from Oregon to Arizona, and especially in California, and that he had only occasionally met with the variety with long straight leaves (the form Lowiana). Dr. Engelmann is unable to separate Lowiana as a species, but refers it to concolor as a variety. In cultivation the form Lowiana is much more widely represented than the species.