CHARACTERS OF TRIBES AND GENERA, ae 
marks it as a very distinct species. In the “United 
States’ Exploring Expedition” it is spoken of as the “ little 
tree Fern.” This presents a great contrast to Osmunda 
regalis and Todea barbara; these produce from their axis a 
dense mass of aerial outgrowing mossy roots, which increase 
in bulk with age, and in which the early axis of the verna- 
tion becomes imbedded, its apex continuing to maintain its 
position on the surface by the successive evolution of the 
fronds, and often producing offsets (cxspitose) ; numerous 
crowns of fronds are thus formed, and which continue to 
develope rootlets from their base, thus gradually increasing 
the size of the spongy mass, By this mode of increase 
specimens of O. regalis attain the height of 2 or more feet, 
` with a diameter about the same, but this is exceeded in ` 
size by Todea barbara, specimens of it having been received. 
in Europe from the Victorian Alps in Australia, one 
.. measuring 5 feet 8 inches in height, its diameter being 7 
feet 9 inches, its weight 1 ton 3 cwt. In 1869 a specimen 
was received at Kew weighing 15 cwt., having 80 crowns, —— 
producing 160 fronds, the weight of these great masses ` 
being due to their being retentive of water like a sponge. 
Division III.—SCAPHOBRYA. 
_ Fronds terminal, rising from between two stipuliform or —— 
socket-like appendages, and articulate with the caudex. ` ` 
_ Sporangia opaque, horny, destitute of a ring. S 
Tribe 28. —MARATTIEJE (Plate 28). 
ManarriAcEz, Kaulf.. 
Vernation terminal, articulate. d 
... Oss.—Although this tribe agrees with the whole of the ` 
| Being in the fronds being spirally developed, it = 
