EUCALYPTUS TREES. 587 
idologists have already unfolded the astounding num- 
ber of 2,400 specific forms, numerous varieties uncount- 
_ed (vide Hook. and Bak. Synops Filic). Yet recent 
searches over the small islands of the Samoan group 
have taught us how greatly this number of known 
ferns may yet be augmented, when once Central 
Africa, Borneo, Sumatra, New Guinea, Siam, and 
other tropic countries, widely unexplored, shall have 
been fully traversed. The Angiopteris presented to 
you here from North-east Australia extends its single 
fronds often to a length of 12 feet or even more. 
Of Passion Flowers now already 231 are on system- 
atic record, far the greater number from the tropical 
regions of America.* We possess, as yet, but few of 
these graceful plants, and must persevere in our ef- 
forts of acquiring more of them, as well for the open 
ground as conservatories. These plants are not only 
quite as gorgeous as any of those which the epheme- 
rous tastes and fashions of the day have brought into 
prominence, but they are infinitely more remarkable 
and instructive, besides far more lasting and grateful 
in culture. Several species, more or less adapted to 
our climate, yield the granadilla fruits, which yet 
ripen in the tropics at elevations 6,000 feet high. 
Almost every one, who possesses a plot of ground, 
' maintains a garden in some form, or, failing this, rears 
a few window or veranda plants. But simultaneous- 
ly, every one, as a rule, evinces a desire of acquiring 
some more accurate horticultural information, and of 
becoming acquainted with some item or the other of 
knowledge relative to the plants around him. This 
applies, with equal force, to the native vegetation, by 
* Dr, Masters, in Transact. Linn. Soc. Lond., 1871. 
