72 BOTANICAL GAZETTE [JANUARY 
Ophioglossum and Lycopodium, it is stated that there is ‘‘no question” that it 
is a secondary condition derived from such a gametophyte as that of Marattia, 
and probably through association with the symbiotic fungus. Of course it is 
known that the green, aerial portion of the gametophyte of certain species of 
Lycopodium is secondary, arising from the previously formed tuberous, sub- 
terranean portion, but it is conceivable that the gametophyte of Ophioglossum 
had a different origin. It is interesting to note in this connection, what may 
be of service to the author’s view, that the gametophyte branches of some of 
the Anthocerotales become tuberous and subterranean, and that this habit is 
not unusual among liverworts. 
n presenting the comparative morphology of Ophioglossaceae and Marat- 
tiaceae, the author has used the greatest variety of structures, but the 
conclusion as to genetic connection seems sound. In some cases the interpre- 
tations are at variance with what have come to be conventional; but, in the 
main, these unconventional interpretations have not so much to do with the 
Fciktions of TS and Marattiaceae as with the primitive character 
of the former among vascular plants. For example, to conclude that a short- 
reasons given, but it is unconventional. There seems ‘3 be no conception of 
However, since the transition region often appears to be merely a place rather 
than a definite structure, perhaps we have been laying too much stress upon it. 
The general conclusion is that “from some form, allied to the simpler 
existing species of Ophioglossum, the whole fern series is descended”; that in 
this series “‘the leaf is the predominant organ, the stem at first being quite 
subordinate in importance”; that ‘this ancestral fern was monophyllous and 
the leaf at first was a sporophyll”’; and that “from this central type presum- 
ably several lines diverged, of which only a few fragments exist.” The detai 
of excare and of lines of divergence are too numerous to cite; but the 
as a whole is essential to every student of pteridophytes.—J. M. C 
Cecidology 
Probably the most important general work on cecidology recently published 
is Ktster’s Die Gallen der Pflanzen4 The author gives a clear and concise 
statement of the theories and problems which confront the botanist. In the 
preface he calls attention to the fact that there is no book on the general subject 
of gall formation, and that the recent literature has demonstrated the necessity 
of studying both the botanical and zoological phases of the subject. He also 
4Kister, Ernest, Die Gallen der Pflanzen, ein lehrbuch fiir Botaniker und 
Entomologen. 8vo. pp. 437. figs. 158. Leipzig: S. Hirze 
