6o 4 STUDIES IN FOSSIL BOTANY 



a fairly advanced Angiosperm, in structure and form 

 correspond to the sporophylls of a Fern, their compound 

 pollen-sacs, or synangia, exactly recalling those of 

 some recent Marattiaceae. It is, however, improbable 

 that these Fern-like characters ' (among which the 

 ramenta must also be reckoned) came to the Bennet- 

 titeae directly from any group of true Ferns. There 

 can be little doubt that the Bennettiteae and the 

 Cycadophyta generally trace their descent through the 

 Pteridosperms, and that it is by their means that the 

 Filicinean features, so conspicuous in the microsporo- 

 phylls, have been handed on to the later group ; the 

 presence of synangia, in particular, can thus be ex- 

 plained. It is certainly a striking fact that this family, 

 so highly advanced in general floral structure and in the 

 characters of the gyna;cium, should have retained, with 

 so little modification, a form of microsporophyll which 

 is essentially that of a Fern. 



The Bennettiteae thus present an extraordinary 

 combination of characters, Filicinean, Gymnospermous, 

 and Angiospermous. Their investigation, as we shall see 

 in the next chapter, has for the first time thrown light 

 . on the great and obscure problem of the descent of 

 the higher Flowering Plants. 



II. CONIFERAE 



The question of the origin and early history of 

 the Coniferae, now the predominant Order of Gymno- 

 sperms, is clearly one of the most important on which 

 fossil botany may be expected to throw light. At 

 present, however, the evidence on these points is 



