On Azolla and Salvinia. £51 



the incrustation, which does not, I think, become organised ; 

 and which moreover, appears somehow or other connected 

 in every instance with the difFormity of the organs. 



In conclusion it appears to me sufficiently plain, that in 

 the higher Acotyledonous plants, in which I include Filices, 

 Lycopodineae, Isoetese, Equiseteae, Marsileacese, Salvinidse, 

 Musci, Hepaticse, Characeae, there are at least two modifica- 

 tions of the female organ representing the modifications of 

 the same organ of Cotyledonous plants. 



The term Pistillum has been applied to the female organ of 

 Mosses by some first-rate Botanists, though not without vio- 

 lent opposition from some systematists. Since the examina- 

 tion of Balanophora, its application is, if possible, still more 

 legitimate. In my opinion it is not to be doubted, that 

 not only have Musci and Hepatica? a pistillum, but that this 

 contains an ovulum.* 



The analogies presented by the plants which form the 

 subject of this communication, to those Cotyledonous plants 

 in which the ovulum is entirely naked, either, as is supposed 

 to be the case in some, without a carpel leaf, or with that 

 organ in an expanded not a convolute state, are I think equal- 

 ly striking. 



It may be worthy also of remark, that in proportion as 

 Acotyledonous plants become, so to speak, less pistilligerous, 

 their vegetative organs appear to be more developed. This 

 is evident if a Fern be compared with a Moss. And it 

 seems to be so closely followed up, that Salvinia which has 

 less, perhaps, of the atropous phasnogamous ovulum than 

 Azolla, has its organs of vegetation considerably more deve- 

 loped. 



* See also Mr. Valentine, Linn. Trans, xvii, p. 466, 67, t. 23, f. 1, 2, 6; where it 

 is stated, that the development of the capsule depends on the presence of the cell 

 (or ovulum) in the pistillum. 



