110 BOTANY OP CONGO. 



be that of the valvular sestivation of the calyx ; for seve- 

 ral, at least, of the genera at present referred to Tiliacese, 

 in which this character is not found, ought probably, for 

 other reasons likewise, to be excluded from that order : 

 and hence perhaps also the Chlenacese, though nearly re- 

 lated, are not strictly referable to the class Malvaceae, 

 from all of whose orders, it must be admitted, they differ 

 considerably in habit. 



LEGUMINOS^. According to Baron Humboldt/ this 

 family, or class, as I am rather disposed to consider it, 

 constitutes one twelfth of the phsenogamous plants within 

 the tropics. Its proportion, however, is much greater in 

 Professor Smith's herbarium, in which there are 96 species 

 belonging to it, or nearly one sixth of the whole collection. 

 And ample allowance being made for the lateness of the 

 season when the collection was formed, which might be 

 supposed to reduce the number of this family less than 

 many of the others, Leguminosae may be stated as form- 

 ing one eighth of the Phsenogamous plants on the banks 

 of the Congo. In India, it probably forms about one 

 ninth, which is also nearly the proportion it bears to 

 Phsenogamous plants in the equinoctial part of New 

 Holland. 



I have formerly proposed to subdivide Leguminosse 

 into three orders.'' 



Of the first of these orders, MIMOSEyE, there are only 

 430] eight species from Congo, seven of which belong to 

 Acacia, as it is at present constituted ; the eighth is a sensi- 

 tive aculeated Mimosa very nearly allied to M. aspera of 

 the West Indies, as well as to M. canescens of Willdenow, 

 found by Isert in Guinea; and perhaps is not different 

 from the species mentioned by Adanson as being common 

 on the banks of the Senegal. 



Of the second order, CiESALPlNE^, the collection 

 contains 19 species, among which there are four unpub- 



' Op. cifat. ^ Flinders' Voy. 2, p. 551. (Jn/e, p. 22.) 



