76 BRITISH EOCENE FLORA. 



more exactly, and to separate them specifically from each other, the name is to remain 

 attached to the form shown in fig. 2 of Plate XVI. 



The species belonging to the Cupressine^e, Taxine^e, and Taxe^e, to be described in 

 the following pages, are somewhat out of their proper sequence, 1 but it appears more 

 convenient to take them now while we are occupied with the Gymnospermae, than to post- 

 pone their publication until that possibly indefinite future when all the Families of Plants 

 shall have been disposed of in rotation, and the inevitable Supplement commenced. 

 Various considerations, geological and paleeontological, of both physical and theoretical 

 nature, had led me to the belief that the determination of the newer Fossil Floras of 

 Ireland and Scotland as Miocene rested upon no sufficient data, and that they might well 

 be of such antiquity as to come within the scope of the present work. Visits to Dublin 

 and Belfast convinced me that the existing collections were wholly insufficient for 

 descriptive purposes ; and, with the aid of a grant from the Royal Society, I have there- 

 fore set to work to obtain an adequate representation of these Floras. This work is still 

 in progress, but the results so far comprise many hundred specimens, and the Coniferae 

 among these, supplemented by others obtained for the Belfast Museum, by that thorough 

 botanist, Mr. S. A. Stewart, are now figured. 



So little is generally known, even to those most interested in fossil plants, respecting 

 the deposits of Ireland and Scotland from which those under consideration are derived, 

 that it will enable us to understand them better and therefore invest them with a higher 

 interest, if I briefly describe their chief geological features here, and the reasons which 

 render it impossible, or at least inexpedient, to exclude these Floras from the present 

 Monograph. The consideration of this question has the additional advantage of bringing 

 home to us the imperfection of our knowledge on all subjects connected with fossil plants, 

 and the futility of attempting as yet to infer from them the relative ages of rocks. It is 

 encouraging, however, to believe that our present ignorance will sensibly lessen as this 

 work progresses ; for, as already pointed out, nowhere else in the known world is so vast 

 a series of plant-remains intercalated among strata whose ages are absolutely known. It 

 would indeed be singular, if some at least among them, when properly determined, do 

 not take rank as landmarks side by side with fossils of the Animal kingdom. 



In England we have not hitherto had to depend much upon plant-remains for our 



1 The publication of the present Monograph, while collecting is still in progress, is attended with con- 

 siderable inconvenience, and its continuity is to a great extent destroyed. This is unavoidable, however, 

 for it must be borne in mind that, as plants are imbedded piecemeal, we are often far from knowing 

 as much of the organism even when many specimens have been obtained, as a single specimen would 

 usually reveal among the Invertebrata. Years of collecting may yield nothing but detached leaves, fruits, 

 or flowers, their connection being merely matter of inference, until some day the exact specimen required 

 to convert inference into fact is unexpectedly discovered. Thus the collection of fossil plants can never be 

 considered complete so long as the beds containing them are accessible, and their description and publication 

 must either be undertaken with these inherent drawbacks or postponed to a time that would ever recede. 



