25* 
A New Book on Palceobotany . 
not only in relating it to the other Equisetalean types, but also in 
the discussion of its relations to the Sphenophyllales and of the 
morphology of the sporangiophore, and under these circumstances 
a new and more correct figure might have been given. The account 
of the Sphenophyllales is perhaps the best section in the book, and 
is probably the best brief summary of this group which has yet been 
written. The interesting Devonian form Pseudobornia is accorded 
a figure and a brief description and is regarded as representing a 
distinct group—the Pseudoborniales. Dr. Pelourde considers the 
Sphenophyllales as constituting a synthetic group more or less 
closely connected to the Pseudoborniales, Equisetales, Psilotales 
and Lycopodiales. 
The sections devoted to the Lycopodiales contain an immense 
amount of summarised information with a great many references 
to the extensive literature on the subject. The author is certainly 
to be congratulated on the way in which he has managed to give a 
survey of so much in such a small space. Sometimes we are 
inclined to wonder what sort of impression this very condensed 
section would produce on the mind of one who was reading about 
these plants for the first time. 
No doubt the fossil ferns present greater difficulties than any 
other group in a book of this type, and the author does not seem to 
have been quite so successful in his treatment of them. This is due 
almost solely to the manner in which the material has been arranged. 
Under the heading Filicales we have a list of the principal classes 
of modern ferns, followed by a description of the various forms of 
fossil fern-like fronds which are known for the most part from 
impressions. The next chapter is devoted to a short summary of 
some of the different types of fern sporangia found in a fossil state, 
including both impressions and petrified forms. Some of the 
sporangia described are only known as isolated structures, while 
others can be connected with the stems of the plants which bore 
them with some degree of certainty, as in the case of Stauropteris 
oldhami. The last section is devoted to the description of the 
anatomical structure of the various forms, where this is known, and 
though in most cases the vegetative parts only are described, the 
sporangia are sometimes mentioned. Probably the author had good 
reasons for dividing up his material in this way, but he undoubtedly 
lays himself open to a good deal of criticism, and the plan usually 
followed of describing consecutively the fronds, sporangia and 
structural features of each genus or group seems greatly preferable. 
Under the system employed here it is necessary to consult the index 
in order to get an idea of the complete plant of such a form as 
Botryopteris or Stauropteris , while the chapter on the fructification 
is robbed of much of its interest, It would certainly seem out of 
date to group together the Palaeozoic fern-like fronds under the 
heading of the Filicales, for as the author notes at the outset many 
of these fronds were pteridospermic. The question as to whether 
the Pteridosperms or the Filices predominated in the Coal 
Measure period is an old one, but there can be no doubt that many 
of the fern-like Carboniferous fronds bore seeds and if no attempt 
is to be made to separate the known pteridosperm fronds from the 
known filicinean fronds the composite group should be placed under 
a separate heading rather than among the Filicales. And it should 
