266 STUDIES IN FOSSIL BOTANY 



inconsistent with the view that the Lycopods are 

 among the most primitive of Vascular Plants. 



On the other hand, the reproductive organs were 

 generally of a very advanced type. With the still 

 doubtful exception of Spencerites, it appears that all 

 Palaeozoic Lycopods of which the reproduction is 

 known were heterosporous, and this applies, so far as 

 our information extends, to the herbaceous as well as 

 the arboreal forms. Lepidocarpon among the latter, and 

 Miadesmia among the former attained, in the evolution 

 of an organ closely analogous to a true seed, a higher 

 level than any existing members of the Class, and 

 rivalled the Spermophytes themselves. 



Recent discoveries appear to show conclusively that 

 Selaginella, at all events, had no direct connection 

 with the Lepidodendreae, but sprang from a distinct 

 and equally ancient herbaceous stock. If any modern 

 member of the Class can claim affinity with the Tree 

 Lycopods of the Palaeozoic, it would appear to be the 

 greatly reduced genus Isoetes} No light has yet been 

 thrown on the ancestry of Lycopodium, which certainly 

 had no near relation to any of the Palaeozoic forms in 

 which the nature of the spores has been determined. 



In spite of the high organisation of the Palaeozoic 

 Lycopods, it is very doubtful whether they have any 

 true affinity with the Seed-plants which some of them 

 simulate, but this is a question which may best be 

 postponed to the concluding chapter. 



1 See Chapter XIV. 



