of true Drynaria, the rest upwards gradually becoming fertile. 
I see no objection to such a union in the group, but it is hard 
to say how these latter differ from Phymatodes. The young un- 
developed fertile frond, indeed, as seen in our reduced figure of 
the Polyp. Heracleum (Plate 1), bears a very close resemblance 
to the fully-developed sterile frond of the present plant; but 
it gradually changes its character, and is terminated by the fertile 
portion. 
P. diversifolium is remarkable among the true Drynari@ in 
having the fertile fronds pinnated, not pinnatifid. Brown was the 
first to detect this species in tropical Australia, where Malayan 
Ferns may be looked for. ‘The present is one among the most 
beautiful of Ferns in the tropical fern-house of Kew, and is 
a species that seems peculiar to the Malayan Archipelago and 
the islands between it and north-eastern tropical Australia, which 
appears to be its western limit. 
Fig. 1 represents a very reduced figure of a tuft, or crown, of sterile and 
fertile fronds of Polypodium diversifolium, By. 2. Caudex, with a small barren 
frond, and a stipes of a fertile frond. 3. Fertile pinna:—natural size. 4. Base 
of a fertile pinna, with sori, showing the venation,—magnified. 
