64 



THE FERN BULLETIN 



treats of the structure of the ancient forms, which is 

 made clear by numerous photographs of the specimens 

 themselves. These are likely to be full of surprises 

 for the student of modern plants who imagines that 

 evolution has steadily added to the complexity of 

 plants. In the structure of the stems, and in the de- 

 tails of the fruiting parts, many of these ancient plants 

 were much more complex than any that exist today. 

 The plants of the ancient world are included in ten 

 great groups, among which are the true ferns, the seed 

 ferns or pteridosperms, the cycads, the lycopods and 

 the horsetails. A chapter is devoted to the past his- 

 tory each group in which the differences and relation- 

 ships are treated at length. The book is therefore one 

 of the best for becoming familiar with the fern flora 

 that once flourished almost to the exclusion of other 

 forms. It is published by the D. Van Nostrand Com- 

 pany, New York, at $2.00 net. 



