CHAPTER XXII 

 SCHIZAEACEAE 



This Family includes, according to Christensen's Index, four living genera, 

 Schizaea with 25 species, Lygodinin with 26 species. Moht'ia with 3, and 

 Aneviia with 64 species. It is of wide distribution, but chiefly within the 

 tropics. Schizaea and Lygodium are widely diffused, but Anemia is almost 

 confined to tropical America, while Mohria is restricted to the Cape and 

 adjoining southern islands. In point of time certain fossil genera, such as 

 Senftenbergia, Klukia, and perhaps Kidstoiiia, have been referred to this 

 affinity. There may be a question as to the correct inclusion of Senftenbergia 

 in this Family, and its consequent re- 

 ference back to the Carboniferous period: 

 but as the Jurassic Klukia cannot be 

 held in doubt, this establishes the exist- 

 ence of the Schizaeaceous type early 

 in Mesozoic time. Whereas in the 

 Marattiaceae and Osmundaceae the 

 radial type of shoot prevails, in the 

 living Schizaeaceae there is a pro- 

 nounced leaning towards a dorsiventral 

 habit. The upright radial type appears 

 it is true in Schizaea, in Mohria, and in 

 most species of Anemia. Frequently, 

 however, the stock is more or less 

 oblique, while in \Anemiorrhiza it has 

 a creeping habit. The extreme is seen 

 in Lygodium, which has a horizontal 

 underground rhizome with bifurcate 

 branching, and it bears its leaves alter- 

 nately upon its upper surface, in two nearly coincident distichous rows 

 (Fig. 436). Rut where the axis is upright or oblique the leaves are disposed 

 in a dense spiral. 



The leaves show great diversity of detail in the different genera, but all 

 are referable in origin to distal dichotomy of a long narrow stipe. In Schisaea 

 there is very marked and repeated equal forking: the shanks may be more 

 or less completely webbed together below, and they bear the fertile segments 

 on their distal ends (Fig. 437). In Lygodium also the leaf-architecture has 

 been traced b}' Prantl to repeated dichotomy {Die Schicaeaceen, Leipzig, 



Fig. 436. The dorsiventral and dichotomous 

 rhizome of Lygodium scandens, with leaves 

 apparently in a single row. (After Vele- 

 novsky.) 



