﻿4 FiLICES. 



FAMILY V. ScIiizaciftCeae. Ring operculiform, crowning the apex 

 of the sporangium. Sporangia either 1 — 2, placed in the axils of imbricate, 

 clasping, scale-like indusia or numerous, but then placed in 2 — 4 regular, 

 naked rows. Diels, 1. c, fig. 192; Hk. Bk., 1. c, tab. VIII, fig. 64, tab. IX, 

 fig. 68. 



FAMILY VI. PoSypodiaceae. Ring incomplete, vertical, the ex- 

 tremities sometimes separated by the stalk of the sporangium only. Sori 

 definite or indefinite and then the sporangia densely crowded over the paren- 

 chyma; indusium wanting or present. (Ring sometimes as in Cyatheaceae, 

 but then the indusium linear and the ferns not arborescent). Diels, 1. c, 

 fig. 57 & 87, D & H; Hk. Bk., 1. c, tab. I, fig. 7, d. 



FAMILY VII. Parkeriaceae. Ring as in Polypodiaceae. Sori 

 indefinite, consisting of many sporangia scattered irregularly along the few, 

 longitudinal veins, protected by the much recurved margin of the frond when 

 young. Diels, 1. c, fig. 178—179; Hk. Bk., 1. c, tab. Ill, fig. 32. 



FAMILY VIII. OjSinundaceae. Ring incomplete, short and hori- 

 zontal or consisting of a roundish, lateral group of thickened cells. Indusium 

 wanting. Diels, 1. c, fig. 203 ; Hk. Bk., 1. c, tab. VIII, fig. 62, c, & 63, b & d. 



h.h. SERIES II. EXANNULATAE. Sporangia without ring. 



FAMILY IX. Mara tt iaceae. Sori consisting of 8 — 24 sporangia. 

 Sporangia free, placed in 2 close, short rows or joined into 2-valved or cir- 

 cular synangia. Diels, 1. c, fig. 239; Hk. Bk., 1. c, tab. IX, fig. 69, 70 & 72. 



«.«. CLASS II. TTJBEI«.ITH[.^LLOS.^%JE. Prothal- 

 lium white, tuberous, hypogeous or immersed in the substratum. 



FAMILY X. Opliiogioiisaceae. Sporangia without ring, rather 

 large, not gathered into sori but placed on much contracted, spicate or pani- 

 culate segments, originating from the base, the centre or the mai'gin of the 

 barren, normal-shaped segment of the frond. Diels, 1. c, fig. 259, A — B k 

 260; Hk. Bk., 1. c, fig. 73—75. 



