ee Bae Eo) 47 
So eee ae e 
1913] CURRENT LITERATURE 169 
sperms are discussed, which as the author points out constituted the charac- 
teristic vegetation of the secondary or Mesozoic period, just as the angiosperms 
are of the present. Here, in accordance with the author’s well known point 
of view, the Cycadophytes receive a very large amount of attention, to the 
practical exclusion of the actually as well as mesozoically much more impor- 
tant Coniferales. 
Beginning with the living cycads, which are remarkably well summarized 
as to their characteristics and distribution, Scott continues with a description 
of the more important features of the mesozoic Cycadophytes, the Bennetti- 
tales. These are elaborated chiefly in connection with the hypothesis revived 
in recent years by WIELAND, that they are the direct ancestors of the angio- 
sperms. Here the distinguished author, so well known for his anatomical 
investigations, pins his faith unreservedly to the externals of their reproductive 
structures. His summary of their angiospermous features is as follows: 
(1) the presence of flowers organized on the same general plan as the typical 
flowers of the angiosperms; (2) the formation of a fruit inclosing the seed; 
(3) the exalbuminous character of the seed. Scortr concludes in regard to 
the Bennettitales and their supposed angiospermous affinities: “They have 
thus proved to fully deserve the name Proangiosperms, which Saporta, by 
a brilliant inspiration, gave to Williamsonia and Bennettites, at a time when 
their stucture was very imperfectly known.” It is perhaps worth while to recall 
in this connection that Asa Gray, who knew his Compositae perhaps better 
than any other person living, referred the genus Williamsonia with conviction 
to the Compositae. Apparently the reproductive structures of the Ben- 
q 
lower angiosperms. Surely here ner pentes 
One of the most interesting chapters is that in which the author deals 
with the fernlike seed plants, which he himself has done so much to rescue 
from oblivion and restore. With characteristic modesty he makes no reference 
to his own contributions in this interesting field. The Medulloseae are appar- 
ently now regarded as more nearly allied to the cycad stock than the Lygino- 
dendreae, thus slowly reversing the opposite conclusion adopted by the author 
in earlier years. 
book concludes with chapters on the true ferns, the club mosses, and 
horsetails (together with sphenophylls), which latter Scort still prefers to 
associate with the fern stock. The closing remarks on the relation of the 
paleobotanical record to the general principles of plant evolution are of par- 
ticular value, most of all the statement as to evolutionary progress being more 
frequently from the more to the less complex and not vice versa, as is too often 
assumed by writers on evolution. Would that Scotr and other English 
=e ere might focus their attention on this principle in dealing wi 
tomical structures!—E. C. JEFFREY. 
