The President's Address. By Duhinfield H. Scott. 141 



in the petrifactions from the English Coal-measures. In one 

 form, very common in certain localities, the sporangia, which occur 

 in crowded sori on Sphenopteroid leaflets, have a most distinct 

 annulus, suggesting that of an ordinary Polypodiaceous Fern, but 

 usually two cells in width (pi. III. fig. 7). 



Fig. 32. — Ptychocarpus unitus, showing Marattiaceous fructification. 

 A, Part of lower surface of fertile leaflet, showing numerous sori or 

 synangia. B, Synangia in side-view. A and B x about 6. After 

 Graud'Eury. C, Transverse section of a synangium, showing seven 

 sporangia united in a riug. a, vascular strand ; b, cellular tissue of 

 central column to which the sporangia are attached ; c, tissue lining 

 sporangia ; e, /, enveloping tissue, x about 60 diam. After Renault. 

 From the Upper Coal-measures of France. 



Another interesting indication of the presence of true Ferns 

 in the Carboniferous Flora is afforded by the case of a petrified 

 sporangium, in which the spores are preserved at various stages of 

 .germination, agreeing closely with the corresponding stages of 

 development in recent Ferns, among which germination within the 

 sporangium is by no means uncommon. In this instance, then, we 



