SCHIZAEACEAE 543 
to a dichotomous branching is not so clear. In the former the lowest pair of 
pinnae are usually fertile, in the latter genus the sporangia may be distributed 
over the whole length of the leaf. 
Hairs are present in all the genera, and in all except Mohria they 
are filamentous, as in the Botryopterideae, Marattiaceae, and Osmundaceae, 
FIG. 300. 
Upper parts of fertile leaves of the genus Schizaca. A=Sch. pennula,Sw. B=Sch. 
bifida, Sw. C, D=Sch. elegans, J. Sm. In D the ultimate segments are more strongly 
magnified. (After Diels, from Engler and’Prantl, Vat. Pflanzenfam.) 
and are sometimes glandular. In MoArza they are no longer filamentous, 
but flattened as scales: this condition, which is characteristic of most Ferns 
of a more advanced type, is readily referable in origin to lateral widening 
accompanied by longitudinal cell-divisions. 
The sporangia are not arranged in sori, but solitary, a number of them 
being borne on each fertile segment. In Schrzaea and Anemia they 
appear when mature disposed in regular rows, one on each side of the 
midrib, on the lower surface of the fertile segments. They may be protected 
