The Present Position of Palaeozoic Botany. 



187 



Carboniferous Flora. The evidence is well known, and needs only 

 the briefest recapitulation here. A number of fructifications, such as 

 Ptychocarpus, Scolecoptcns, Asterotheca, Haivlea, etc. (see Fig. 17) agreeing 

 closely with the synangia of recent Marattiaceae. have been found 

 in situ on fronds of the Pecopteris type. In some cases the minute 

 structure of the fructifications can be studied in petrified specimens, 



Fig. 17. Group of Fructifications of Ferns or Pteridosperms. A, 1, 2. 3. Asterotheca 

 (Marattiaceoiis ?). B. 1, 2. ReHaultia (affinities doubtful). C, 1, 2, Dactylotheca 

 (doubtful). D, Sturiella, in section; a, bundle; b, d, annalus; c, hairs (cf. Corynepteris). 

 E, Oligocarpia (cf. Gleicheniaceae). F, Crossotheca {cf fructification of Lyg-inodeudreae). 

 G, Senftenbergia (cf. Schizaeaceae). iH, Haivlea (Marattiaceous?). J, 1, 2, Urna- 

 topteris (affinities doubtful). After various authors. 



and entirely confirms the inference drawn from external characters. 

 It would be difficult, in fact, to find clearer evidence of affinity 

 between a recent and a fossil group of plants than is afforded by 

 these synangia. But this is not all: a number of petrified stems, 

 constituting the genus Psaromus. are known, in which the anatomy 

 has been fully investigated, and proves to agree more nearly with 

 the structure of Marattiaceae than with that of any other group of 



