FOSSIL BOTANY 295 



It is an ugly fact that, tempting as is the study of Fossil 

 Botany, every competent botanist with a large knowledge 

 of existing floras, and that has tried his hand on it, has given 

 it up, notably Brown, Brongniart, and Lindley, or these have 

 subsequently confined themselves to specimens exhibiting 

 structure, as fossil wood, &c. whilst Oliver, Bentham, &c. 

 have only shaken their heads when asked to identify a fossil 

 plant. If you are ever at the Herbarium and will look at 

 the multitudes of figures of leaves in Gardner, Lesquereux, 

 and other works, the vagueness of the identifications will 

 strike you at once. There is a standing joke at the Herbarium, 

 if you have a plant the affinities of which puzzle you, ' fossilize 

 it and send it to a palaeontologist and he will give you the 

 genus and species at once.' 



To sum up, in a general way the work of Vegetable 

 Palaeontologists has thrown much light on the older floras 

 of the globe, but far too much is made of the supposed facts, 

 which in detail are wholesalely unreliable. 



With regard to Salisburia, I was the first to show the 

 strong resemblance of the Coal Measure fruit called Trigono- 

 carpon to that of Salisburia, founded on a careful comparison 

 of the tissues of the several layers of the fruits obtained by 

 slicing silicified specimens of Trigonocarpon and fresh ones 

 of Salisburia (published in ' Phil. Trans.') but I am quite 

 prepared to find the same tissues in Cycadeae, in Podocarpus, 

 in Dacrydium, in Cephalotaxus and other genera ! Had 

 leaves of Salisburia occurred with Trigonocarpon the evidence 

 would be good. As it is, possibly Salisburia fruits occur in 

 the Coal ; and abundant Salisburia leaves occur (not in the 

 Coal) but in tertiary rocks without Trigonocarpon. 



I have myself tried my hand on the identification of 

 fossil collections of plants by their leaves, &c. and what I 

 find is this, you have, say 100 forms of leaves from one 

 bed, evidently belonging to many genera and families. You 

 identify one of the most peculiar with a plant of Japan we 

 will say. Well, you have no difficulty in matching all the 

 others with plants of Japan, and you conclude that you 

 have an old Japanese Flora. But if you had started with a 

 S. American identification, and had an equal knowledge of 

 S. American plants, you would have been as successful 

 probably more so for the simple reason that the forms of 



