XXII] 



SPORE-PRODUCING MEMBERS 



169 



sporangia were also marginal as in the living Schizaeaceae, and had originally 

 a more complex annulus than is usually seen in those of the present day. 

 In this connection the fossil Kidstojiia from the Coal Measures of Asia Minor 

 has a special interest (Fig. 454). This, as well as other genera, may be com- 



Fig. 453- Kliikia ixilis (l'lulii)ps) Raci- 

 ijorski. Feilile pinnule of the last order, 

 seen from below. ( x 20.) From the 

 Jurassic of Krakau. (After Raciborski, 

 from Engler and Prantl.) 



Fig. 454. A — 'i. sporangium oi Lygodium lanceo- 

 latum Desv. (X50), showing an annulus of 

 more than a single row of cells. B = Kidslonia 

 heradietisis Zeiller, lateral view of sporangium. 

 ( X 50.) C = Schizaea, apex of sporangium with 

 distal wall ("Platte") of many cells. Z) = ditto of 

 Anemia. [A, ^, after Zeiller: C, D, from Engler 

 and Prantl.) 



pared also with the Osmundaceae on the ground of sporangial structure 

 (Seward, Fossil Plants, ii, pp. 325, 340). They are characterised by having a 

 less specialised, but still an indurated, annulus. Pending a knowledge of further 

 details they may probably be best referred to an indeterminate position 

 among such early Ferns: but their existence appears to strengthen the 

 comparisons of the Schizaeaceae downwards with the Osmundaceous, and 

 ultimately with some Botryopterid or Zygopterid type. (Compare Zeiller, 

 Bull. Soc. Bot. de France, xliv.) 



On the other hand, certain fossilsof later time have been referred tentatively 

 to the Schizaeaceae. For instance, Teuipskya Knowltoni Seward, from the 

 Lower Cretaceous of Montana. Professor Seward has discussed this in 

 detail, together with various other fossils, such diS Ruffordia from the Wealden, 

 which maybe assigned provisionallytoa like affinity (.-J ;/«.t^/i)(?/. p. 485, 1924). 



The development of the Schizaeaceous sporangium follows the usual 

 Fern-type in its main features, the essential parts of each, though perhaps 

 not the whole of it, being referable to a single parent-cell with a rectangular 

 base. In all the Schizaeaceae the first segment-wall extends from the outer 

 to the iniler periclinal wall of this cell: such a segmentation is characteristic 

 of the more robust types of Fern-sporangium (Fig. 455). This event is 

 followed bv two other anticlinal divisions as seen in section, and then comes 



