THE REUVERIAN FLORA. 



As soon as we attempted to identify the Reuverian plants, we found before us 

 a flora whose elements were almost unknown, though they suggested an even closer 

 affinity to the flora of eastern Asia than the plants from Tegelen, already described 

 by us. The few European and Chinese forms we could recognise led us to think that 

 we must search the whole palaearctic region for the remainder. Finding our own carpo* 

 logical collections quite inadequate, we examined as many palaearctic species as we 

 could in the Kew Herbarium. Through the courtesy of the authorities we were enabled 

 to make working drawings of a very great number of fruits, endocarps, and seeds 

 belonging to palaearctic genera. In this way preliminary determinations were made 

 which we checked afterwards by microscopic examination, and comparison side by side 

 with the recent specimens. For enabling us to carry out this part of the work we must 

 thank the Director and staff at Kew, who provided us with specimens for comparison, 

 dissection, and photography. 



As the work proceeded it became evident that our search must extend beyond the 

 palaearctic boundary, and we carried it into certain American, Malayan and Australian 

 genera, if we had reason to think that our fossils had relationship with them. Unfor* 

 tunately time and opportunity would not serve to carry out this part of the research 

 fully, and it is quite possible that some of our unknown forms may have this wider 

 range. We think it more probable however that their alliance is with Chinese species 

 to us unknown, though some may belong to extinct genera. 



The Reuverian flora already includes nearly 300 species. Of these we have been 

 able to suggest the botanical position of about 230 with some degree of certainty, and 

 of a lesser number, rather more than half the known flora, with considerable certainty. 

 Various causes have militated against the specific determination of many of the species — 

 lack of material, fossil or recent, for dissection, the fragmentary state of some of the 

 fossils, or more often the fact that they belong to immense orders or genera, or to those 

 with very minute seeds. Among such we may count Umbelliferae, Labiatae, Carex, and 

 Hypericum. The labour involved in the determination of such forms is prohibitive, 

 except where access can be had to a world-wide carpological collection, arranged for 

 convenience of microscopic study. Unfortunately in England we have as yet no such 

 collection ; consequently material has to be laboriously searched for and prepared from 

 the sheets of herbarium specimens. 



Though our specific determinations only represent a part of the Reuverian flora, 

 they yet prove some remarkable facts. On examining the list of trees and shrubs, which 

 form the most peculiar and striking element in this flora, we find a surprising resem? 



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