Bower . — Studies in the Phytogeny of the Fiticales. VI. 39 
6. The genus Leptochilus , as at present defined, may probably be 
a composite genus, not a phyletic unity. 
7. The Acrostichoid condition has been acquired along a very con- 
siderable number of distinct phyletic lines. Accordingly Acrostichum 
connotes not a genus in the sense of a phyletic unity, but a condition 
or state, which has been arrived at from various distinct sources. 
DESCRIPTION OF FIGURES ON PLATES I AND II. 
Illustrating Professor Bower’s paper on Ferns showing the * Acrostichoid’ Condition, &c. 
PLATE I. 
Fig. 1. Whole plant of Gymnopteris tricuspis (Hook.) Bedd., one-sixth of the natural size. 
Fig. 2. Whole plant of the same, showing additional helicoid branching of the sterile leaf. 
From the Edinburgh Botanic Garden. Photograph supplied by the Director, through Dr. 
R. C. Davie. 
Fig. 3. Base of the fertile lamina, natural size, showing the branching and the soral areas. 
Fig. 4. Neocheiropteris palmatopedata (Bak.), Christ. Specimen in Glasgow University Her- 
barium, showing helicoid construction. Half natural size. 
Fig. 5. Base of the fertile lamina of Neocheiropteris , showing the branching and sori. x 2. 
Figs. 6, 7. Leaves of Polypodium ( Phymatodes ) decumanum , Willd., for comparison of branching 
with Gymnopteris tricuspis. Half natural size. 
PLATE II, 
Fig. 8. Leptochilus latifolius (Meyen), C. Chr. Sterile and fertile leaves, half natural size, for 
comparison of the branching with Gymnopteris tricuspis. 
Fig. 9. Part of an old fertile pinna of Metaxya , showing the venation and the sori (from which 
the sporangia have mostly fallen away), more than one sorus being on the single vein, x 2. 
Fig. 10. Part of a pinna of Metaxya, with mature sori. x 2. 
