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difk being often male, or containing only 
ftarnens. The difk and ray are the terms 
made ufe of to exprcfs the centre and cir- 
cumference, and are frequently applied, with 
the fame meaning, to the compound flowers. 
In the fimple flowers of the clafs Pentandria 
there are fome genera the fpecies of which 
differ fo much in fome parts of their fructi- 
fication, that it may be neceflary to apprize 
the young botanift of this diffimilarity. The 
gentianella and lefTer centaury, both placed 
by Linneus under the genus Gentiana, are 
fo unlike in their appearance as even to per-? 
plex an experienced botanic eye. The 
flructure of thofe fpecies of Gentiana, which 
are known by the name of Gentianella^ is 
fo peculiar as to feem to give them a right 
to form a feparate genus ; and the centaury 
is now placed by Mr. Curtis in the genus 
Chironia, from the circumftance of the 
anthers becoming twilled after they have 
feed their dull, a diftinguifhing character of 
the Chironia genus, alfo from the fimilarity 
of their outward habits. Such refpe&able 
authority as that of Mr. Curtis muft have 
great weight; and all who underftaixd the 
valuta 
