APPENDIX. No. V. 479 



Cassytha pubescens Prodr. Flor. Nov. Hydrocotyle asiatica L. 



Holl. Hedysarum adscendens Sw. 



Celtis orientalis L. . Hedysarum vaginale L. 



Cardiospennum grandiflorum Su: Pterocarpus Ecastopliyllum L. 

 Paullinia pinnata L. 



On these lists it is necessary to make some observations. 



1st. The number of species in the three first hsts taken together is equal to 

 at least one-twelfth of the whole collection. The proportion, indeed, which 

 these species bear to the entire mass of vegetation on the banks of the Conoi) 

 is probably considerably smaller, for there is no reason to believe that any of 

 tliem are very abundant except Cyperus Papyrus and Bombax pentandrum, 

 and most of them appear to have been seen only on the lower part of the river. 



2nd. The relative numbers of the species belonging to the primary divisions 

 in the lists, is analogous to, and not very materiall)' different from, those of the 

 whole herbarium ; Dicotyledones being to Monocotyledones nearly as 3 to 1 ; 

 and Acotyledones being to both these divisions united as hardly 1 to 16": 

 hence the Phfenogamous plants of the lists alone form about one-thirteenth of 

 the entire collection. 



The proportions now stated are very different from those existing in the cata- 

 logue I have given of plants common to New Holland and Europe;* in which 

 the Acotyledones form one-twentieth, and the Phaenogamous plants only one- 

 sixtieth part of the extra-tropical portion of the Flora ; while the Monoco- 

 tyledones are to the Dicotyledones as 2 to 1. 



The great proportion of Dicotyledonous plants in the lists now given, and 

 especially in the two first, which are altogether composed of American species, 

 is singularly at variance with an opinion very generally received, that no well 

 estabhshed instance can be produced of a Dicotyledonous plant, common to 

 the equinoctial regions of the old and new continent. 



3d. The far greater part of the species in the hsts are strictly equinoctial; 

 a few, however, have also been observed in the temperate zones, namely 

 Agi'ostis virginica, belonging, as its name imphes, to Virginia, and found also 

 on the shores of Van Diemen's Island, in a still higher latitude ; Cyperus 

 Papyrus, and articulatus, Nymphaea Lotus, and Pistia Stratiotes, which arc 



* Flinders' toy. 2. p. 593. 



