112 



THE VOYAGE OF II.M.S. CHALLENGER. 



The relatively large proportion of Leguminosse, amounting to over 13 per cent, of the 

 whole, may be accounted for partly by the fact that several of the species of this Order are 

 commonly cultivated, and have thereby become so widely diffused in a wild state, and 

 partly by the fact that the seeds of many members of this Order will bear long immersion 

 in sea water without losing their vitality, and often germinate when cast ashore after 

 having been conveyed long distances by oceanic currents. 



With regard to the proportions of the various natural Orders, it is very probable that an 

 analysis of the complete flora of these islands would give very different results, for we 

 know that the present collections are almost entirely composed of the littoral element. 

 Nevertheless, the analysis given by Decaisne 1 of the flora of Timor offers very similar 

 proportions. The total number of species enumerated by Decaisne is 550, whereof 100 

 are monocotyledons and ferns, leaving 450 dicot)'ledons, representing a large number of 

 genera and natural Orders ; the Orders (including ferns) most numerously represented 



It will be seen that the natural Orders are nearly the same in the two instances. Ferns, 

 if included, would occupy a similar position in our flora. Taking the other Orders not 

 among ours, represented by ten or more species, the numbers are : — Myrtaceae, 7 ; Buett- 

 neriaceae, ; Solanaceae, 8 ; and Cyperaeeae, 2 ; in the present collection from the South- 

 eastern Moluccas. Of these Orders the Cyperaceae are perhaps the likeliest to receive a 

 considerable accession to the present number in future collections. It should be mentioned 

 that Decaisne retains the Artocarpese as a distinct Order from the Urticacece, and of the 

 former he describes thirteen species, eleven of Ficus and two of Artocarpus. 



Examining the distribution of the plants in the foregoing table, we find that out of the 

 367, 274, or about 74 - 7 per cent., extend to Continental Asia ; 193, or about 52 - 6 per cent., 

 to Australia ; 165, or nearly 45 per cent., to Africa ; 137, or 37 per cent., to Polynesia ; and 

 107, or 29 per cent., to America. Taking the Malayan Archipelago as one geographical 

 area or region, 35 out of the 367 are restricted to it; in other words, 332 out of 367 

 extend to one or more of the other geographical areas. The number extending to three 

 areas is 227 ; while 165 are spread over four areas, and 109 over five areas. Finally, 

 48 of the species, or 13 per cent., occur in all six areas. These are : — 



Portulaca oleracea, Sida rhombi folia, Urena lobata, Hibiscus tiliaceus, Thespesia 



Herbarii Timorcnsis Descriptio, p. 8. 



2 A tribe of Sterculia^ece, not represented in our collections. 



