It is impossible to estimate the good which the modern catalogue does in spreading substantial information. In this before us a species of every genus is given in illustration, so that people at a glance can have an idea of what the whole genus is like. Some of these catalogues which people get for nothing are often worth more, in a botanical point of view, than old-fashioned treatises that cost a great deal of money to procure. Of course they are not always up to the latest botanical rules, as, for instance, Bartonia as here given, the botanist would call Mentzelia; but for useful pioneer work they cannot be excelled.