TO BOTANY. 



The regularity of the petals is not so much to be 

 depended on as some former botanists* have thought; 

 for we see in Geranium the European species have 

 regular corollae, but the African ones irregular. 



The mctarmm nature has made of the greatest con- 

 sequence. This part, which had not even a name 

 till Linnaeus had distinguished it, is a decisive mark 

 in all the following genera, viz. in Orchis, Satyrium, 

 Monotropa, Fumaria, \ 7 'iola, Malpighia, Banisteria, 

 Adenanthera, Commelina, Lauras, Helxine, Dic- 

 tamnus, Zygophyllum, Swertia, Lilium, Fritiilaria, 

 Hydrophyllum, Ranunculus, Hevmannia, Berberis, 

 Staphylea, Passiflora, Narcissus, Pancratium, Mi- 

 rabilis, Nerium, Stapelia, Asclepias, Diosrna, Cam- 

 panula, Plumbago, Hyacinthus, Rhododendron, 

 Cheiranthus, Sinapis, Kiggelaria, Cluytia, Aqui- 

 legia. Nigella, Aconitum, Parnassia, Epimedium, 

 Theobroma, Reseda, Grewia, Helleborus, Isopy- 

 rum, Tropaeolum, and Impatiens. 



The stamina and calyx, being less subject to 

 luxuriancy, are far more certain than the petals. 



The corolla varies as to its figure in many genera ; 

 as in Vaccinium, Pyrola, Andromeda, Nicotiana, 

 Menyanthes, Primula, Veronica, Gentiana, Hya- 

 cinthus, Scabiosa, and Narcissus. It varies also as 

 to number, being, in Ranunculus, pentapetalous in 

 some species, and polypetalous in others ; in Helle- 

 borus, also, pentapetalous and polypetalous ; in Sta- 

 tice, pentapetalous and monopetalous ; and in Fu- 

 maria, dipetalous and tetrapetalous : and the num- 

 ber is also sometimes variable in the same species, 

 as is observed in Carica, and Jatropha. 



The structure of the Pericarpium was formerly 

 thought to be of great consequence in determining 

 the genera ; but there are examples without number 

 that demonstrate the contrary. There are a great 

 many genera that have been established on distinctions 



* Rivinus, in particular. 



