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Variation patterns and interpopulational relationships were examined in Linum lewisii Pursh and L. pratense (Norton) Small, the two native North American blue-flowered flax species. The two principal evolutionary trends in the North American populations have been toward self-pollination and an annual life habit. A third trend, toward greater outcrossing, is considered probable. Hybridizations between and within species indicate that evolution has occurred mainly by the accumulation of small genic changes in geographically isolated populations. The buildup of sterility barriers between populations regardless of species has not been extensive and in no case do hybrids have less than 30% good pollen. In general, morphological evolution has occurred independently of the buildup of sterility barriers. A new taxonomic combination, L. lewisii ssp. lepagei (Boivin) Mosquin, is adopted.

IN the Proceedings of the Academy of Natural Sciences of Philadelphia for 1902, pp. 33–36, is a very interesting paper by the late Mr. Thomas Meehan, treating of some points in the life-history of certain plants. On p. 36, Mr. Meehan says:—“Mr. Darwin once stated that one might as well use organic dust as to endeavour to get seeds of Linum pereune by the aid of its own pollen. I found Linum pereune of our Rocky Mountains abundantly fertile with own-pollen, and said so in one of my papers.” As some anti-Darwinian will probably make much of this statement, it is as well to say that the Rocky Mountain plant is a distinct species, Linum lewisii, Pursh.