Incoming correspondence to George Engelmann from Thomas Meehan, for 1859-1883. The correspondence relates to the development of embryos, fertilization, fruiting; production of male and female flowers. Morphology of impregnation of pines. Cultivation and observations of plants for Engelmann. Theories on plant development reproducing the sequence of evolutionary development with observations. Theories on wood formation, bark formation. Academy of Sciences. Theories on bud development with observations; flowering times. Variation within species rather than separate species. Biographical information Publication of Illustrations. Theories and observations on timberline, grasses, soil retention, elevation.

Folder contains original letters.