Hexandria Monog.  Littea. 
by a difference in habit (if such exists) ought 
not, or rather does not, constitute a true genus. 
For, it must continually be kept in mind, that 
it is not a botanist that actually makes genera. 
No: he merely attempts to discriminate those 
which the mighty hands of his own Maker have 
already made ;—and not only made, but sealed, 
each with marks peculiar to itself, which we di- 
stinguish by the name of habit, and by 9rhich 
alone it is possible to know them. Where is the 
botanist who cannot, without florescence, 
o 
us 
Cereus from Opuntia, or Rhipsalis from Per 
skia or Epiphyllum ; however close those liler 
tribes approach in their inflorescentia? The 
woody axis alone, where we can dissect for it, 
will MM separate Cereus from Cacti too 
young to beromri of down. Even Cras. 
sula be told from Cotyledon by habit alone; 
may 
and Sedum from Sempervivum ; however diffi- 
cult these tribes are to separate by inflorescence., 
Such are Nature's genera; and none but such are 
real. 
The author is nevertheless aware that in thus by- 
ing so extensive a stress on the validity of ha- 
bit, as a leading feature in the foundation of 
genera ; he is raising a host of botanists against 
him: for one of the most laborious and. judi- 
cious amongst us, and no enemy even to the mul. 
tiplication of genera, has long sincé exclaimed 
against those of such construction, **ez facie, 
potius quam charactere," in his Prodrom 
Stirpium in quee ad Chipel Allerton, p. 24k. 
At such words, and from such a Source, the au- 
thor confesses he feels abashed, For, notwith; 
