360 



ORDER NYMPH ACE^. 



which in time changes to the oblong scarlet berry of the common 

 Berberry, which genus of course belongs to the Linneean class 



FIG. 133. EPIMEDIUM ALPTNUM, AND BERBERIS SIBEHICA. 



HEXANDRIA, and order Monoggnia. The British Epimedmm 

 or Barren- wort, however, possessing only four stamens, is referred 

 to the class TETRANDRIA ; but there is a North American species 

 which conforms to the general type in possessing six stamens. 



520. Another order which may be briefly noticed, is that of 

 NYMPHACE^E, the Water-Lily tribe ; the two common species of 

 which, the White and Yellow Water- Lily (belonging, however, 

 to different genera) are sufficiently well known. Much con- 

 troversy has taken place, as to whether this order is to be ranked 

 amon^ Exogens or Endogens, as its herbaceous stem does not 

 afford the means of satisfactory determination, and the structure 

 of its leaves is such as might agree with either group. Here, 

 however, the number of the parts of the flower, which are 

 arranged in fives, affords important assistance ; and, in spite of 

 some general resemblance which the Water-Lilies bear to the 

 Water-Plantains, this fact would lead us to rank the order with 

 Exogens, of which the number five is characteristic, whilst it 

 never presents itself in Endogens. The structure of the seed 

 confirms this conclusion ; for the embryo is a little dicotyledonous 

 body, enclosed in a peculiar bag which separates it from the 



