3$ 2 French Na I tonal Ins titute, 



and he conduces that the nelumbo docs not differ essen* 

 lially from the other plants of its class. 



M. Correa, although he agrees with M. Mirbel that the 

 nelumbo is a plant with two colvledons, does not share in 

 his opinion respecting the nature of the lobes : he thinks, 

 withGasrtncr, thatthese organs have a considcrablearialogy 

 wiili the vitcllus, and he compares thcn» with the fleshy 

 tubercles of the roots of the orchis. The plants, as this 

 learned botanist observes, have a double and relative organic 

 zalion. — on the one hand, wiili the earth in which they 

 ought to take root, and on the oiher hand, with the air 

 in which their folia 2:e is developed; the roots as allotted 

 to the ascending vegetation, and the leaves to the descend- 

 ing vegetation ; and it is at the point where these two sy- 

 stems of organization unite, that the cotyledons are gene- 

 rally placed : — Now the lobes of the nelumbo arc at the most 

 inferior part of ihe plant, and consequently m the svstem 

 of the ascending vegetation, or of the roots. This view of 

 regarding the neluuibo would indeed take away the means 

 of recognising the cotyledon;* in it ; but the example of 

 many other plants deprived of these organs, shows that 

 they are not at ail essential to vegetation, and that the cha- 

 racters which have been derived from them, in order to 

 separate the vegetable kingdom into three divisions, are 

 insufficient, and that they ought to be replaced by those 

 which give the direction of the vessels and the medullary 

 radii. 



It is also with the view of dispelling the doubts arising 

 from the differeiU opinions of several learned botanists, that 

 M. Poiteau has undertaken a work, which he has submitted 

 to the Classy on the germination of the Graniinere. Bota- 

 nists were not agreed as to th^ part of the seed ot th-, se plants 

 which ought to be regarded as the cotvledon ; but ('bserv- 

 -^ ing that the escutcheon, which Gyertner took for a viiellus, 

 and M. Richard for the bodv of the radicle, was placed in 

 tiie point where the pluniiiie and the radicle separate, 'he 

 considers thisorgan as a true cotyledon, riiese inquiries 

 have besides led M. Poiteau to an observation, which, al- 

 tliough accidental, is not the less interesting, since it is 

 connected vvith one of the pha^nomena which are n)ost ge- 

 neral in vegetation. At the nioment when the radicle of 

 the (jrannneae is fleveloped, it takes the figure of a(one, 

 and .represents the principal root or tiie pivot of the other 

 plants ; but soon afierwards, and the instant the lateral 

 roots acouire a certain growth, this cone is obliterated and 

 de&troyed, so that no plant of this family has a pivot : aifd 



as 



