TETRAXDRIA AXD PENTASTDRIA. 



155 



Fig. 308. 

 TetrandiaTetragynia. Tetrandia Digynia. 



CLASS IV TETEANDRIA. 



The flowers in this class have four stamens, and one, two, or four pistils Mono- 

 gynia, Digynia, and Tetragynia. It is not an extensive class, having only twenty-two 

 genera and sixty-five species ; and of these the large majority are valueless weeds. 



The order Monogynia is 

 the largest, and contains 

 fifteen genera, four of which 

 have no petals viz., Al- 

 chemilla, or Lady's-mantle ; 

 Sanguisorba, Isnarda, and 

 Parietaria ; whilst nine are 

 monopetalous, and two are 

 polypatalous, with four 

 petals. There are seven 

 genera, possessing four pis- Fig. 309. 



tils, and amongst them the Holly, Hex, Lime-tree, Tilia, and Pond Tetrandria Monogynia. 

 weed Potamogeton. A few plants are supposed to possess medicinal properties, as the 

 Rubia, or Madder ; Galium, or Bed-straw ; and Sanguisorba officinalis, or Great Burnet. 

 The Dipsacus Fullonum, or Fuller's teazel, the hairs of which (Fig. 113) are so useful 

 to clothworkers, belongs to this class. Several other members possess a certain 

 degree of beauty as the Scabiosa and the Ilex, which is the cheering emblem in our 

 Christmas festivities. The most numerous plants, under this head, are the Plantago, 

 or Plantain, with its spike of sessile flowers, the Alchemilla, and the Potamogeton. 



CLASS V. PENTANDRIA. 



This is a most important, numerous, and varied class of plants, and has ninety-four 

 genera and two hundred and ten species. The plants have five stamens, and one, two, 

 three, four, five, six, or an indefinite number of pistils (Polygynia). It is not possible 

 to give any one expression which shall represent this class as a whole ; but there are 

 many of its members which may be arranged together both in structure and properties ; 

 so that the class is a compound of several bodies or classes of plants. 



The order Monogynia is very extensive, comprehending no fewer than forty genera. 

 Thirty-one of these have monopetalous corollas ; six are polypetalous of five petals, and 

 three are apetalous. Ten genera are closely associated together, as 

 shown by having inferior monopetalous flowers with two or 

 four naked (so-called) seeds, and a covering of rough hairs over 

 the plant. Such are Symphytum or Comfrey, Echium, Borago, 

 Anchusa, or Alkanet-root, Cynoglossum, and the sentimental Myo- 

 sotis or Forget-me-not. This is a compact and well-defined body 

 of plants. Fifteen other genera are distinguished from the above, 

 by having the seeds more manifestly inclosed in a seed vessel; 

 and amongst these are the beautiful Primula or Primrose, and 

 Cowslip, Menyanthes or Bog-bean, Anagallis, Convolvulus, Polemonium or Jacob' s- 

 ladder, Vinca or Periwinkle, and Verbascum ; as also the poisonous Atropa, Belladonna 

 or Deadly Night-shade, the Hyoscyamus and the Solanum Tuberosum, with its poi- 

 sonous berries and edile subterranean stem, known as the Potato. 



The six genera, with superior monopetalous flowers, are of mixed characters, and 



Monogynia. 



