642 Evolution in the Vegetable Kingdom. [July, 
rejected theories would naturally lead and had actually led M. 
Brongniart and others. The authors say: “Of a still more ques- 
tionable character is the theory of progressive development, as 
applied to the state of vegetation in successive ages. In the 
vegetable kingdom it cannot be conceded that any satisfactory 
evidence has yet been produced upon the subject; on the con- 
trary, the few data that exist appear to prove exactly the con- 
trary.” All the denials and assertions made in the work opposed 
to Brongniart’s teachings are made to support this view. The 
existence of Cactaceze, Euphorbiacez and other dicotyledons in 
the Carboniferous would negative development; the admission of ` 
a former tropical climate was a strong argument for the nebular 
hypothesis as well as for geologic progress; tree-ferns would 
argue such a former tropical climate; if Calamites could be 
shown to bea Juncus, a higher type would be found in Paleozoic 
strata than Brongniart believed to occur. Still another good point 
was thought to be gained by proving what is now admitted, viz., 
that coniferous plants occur in the coal. All botanists then held, 
as many still hold, that the gymnosperms were a subclass of the 
dicotyledons, coérdinate with the dicotyledonous angiosperms 
But, curiously enough, Brongniart had forestalled this argument 
by making the gymnosperms of lower type, intermediate between 
the cryptogams and the angiospermous phanerogams. By a 
special insight, characteristic of true scientific genius, he had 
used their lower geological position as a proof of their lower 
organization, z. ¢., had postulated evolution as an aid to organic 
research—a method which is now becoming quite common, al- 
though unsafe except in the hands of a master, 
Dr. Lindley laid much stress upon the fact “that no trace of 
any glumaceous plant has been met with even in the latest Ter- 
tiary rocks,” thus freely employing the fallacy which he else- 
where warns others to avoid, that because a class of plants has 
not been found, therefore it did not exist at a given geologic 
epoch. But to cut off the possibility of a reply to the position 
he takes he finally declares that “ supposing that sigillarias and 
stigmarias could really be shown to be cryptogamic plants, and 
that it could be absolutely demonstrated that neither Conifer 
_ for any other dicotyledonous plants existed in the first geological 
__ age of land plants, still the theory of progressive development 
5 : would be untenable, because it would be necessary to show that 
