Part 91. Flax as a sample type. De Candolle, one of the most learned of French botanists, was wont to say that he could teach all he knew of botany from a handful of plants. What he had in mind was doubtless the great truth that among the resemblances of plants to one another there are some of such fundamental importance that it becomes possible to discern amid the endless variety of forms a few plans of structure upon which all plants are built. His handful of specimens would have been so chosen that each might exhibit especially well the features common to many kinds, and thus serve at once as a convenient standard of comparison and as a means of teaching truths of very wide application. A form which in this way is representative or typical of any group, naturalists call a type.

Flax (Figs. 217 I, II) will serve well as our type of phenogams or seed-plants because it possesses all the parts which they commonly show, and exhibits them in comparatively unmodified condition. Like all true flowering plants it produces seeds.