LESSON VI. ASSIMILATION (concluded)—SUBSTANCES MADE IN THE GREEN FACTORIES. We have talked much in our last two lessons about the sub- stances taken in by plants, and the unwearying activity of the green leaves in preparing these “raw materials†and manufacturing out of them all that is required for the plant’s daily growth and future needs. We peeped into some of the store-houses, and saw that they were full of nutriment; and perhaps it occurred to you to wonder if it would be pleasant to be asked to dinner by the plant, and supplied with food from its hospitable store ! I think the answer to that question must entirely depend on the plant which invited you. An invitation from some would mean nothing less than sudden death to you! From others you might safely accept hospitality. You see it will be wise to learn something of the nature and properties of different plants before tasting any part of them Some of them are busy preparing substances which become most valuable medicines when properly and carefully used; but often these are deadly poisons if taken ignorantly and without precautions as to quantity, ete, ‘To chew the leaves of the foxglove or the purple monks- hood would be exceedingly dangerous and very probably fatal, yet most valuable medicines are obtained from these two plants. Bitter quinine and bark, nasty rhubarb, castor oil (useful But not agreeable), senna for our “black draught,†ipecacuanha for our coughs, laudanum to soothe our pain—