156 ONOCLEOID FERNS [ch. 



It has a massive stock, showing a wide-pithed dictyostele, and a binary 

 leaf-trace (see Studies IV, Text-fig. 2). The axis and rachis are scaly and 

 the leaves dimorphic, the sporophylls closely resembling those of J/, orientalis, 

 but they are shorter. Their details also correspond, excepting in the absence 

 of the indusium. Early stages of development of the sorus show no sign of 

 it (Fig. 683). The sori are superficial, of distinctly intra-marginal origin, and 





s ^ 



Fig. 682. Matteiiccia intermedia C. Chr. Habit of Fern as grown in Glasgow Botanic Garden, 

 but showing only sterile leaves. (Much reduced.) 



with a gradate sequence of the sporangia: moreover, sections parallel to the 

 margin show that they are disposed in strictly regular rows, one row on either 

 side of the mid-rib (Fig. 683, C): and the individual sori are in close juxtaposi- 

 tion. Both in structure and arrangement the sori compare closely with those of 

 Alsophila, where also the sori often show a regular alignment. The sporangia 

 are relatively complex, and compare most nearly with those of Lophosoria 

 (Fig. 684). The annulus, which shows slight signs of obliquity, consists of over 

 50 cells, as against about 40 in Lophosoria (compare Vol. II, Fig. 551), and 



