IQO 



NATURE 



{June 20, 1878 



Austria, Italy, Switzerland, and America, no work of any 

 importance has appeared in England. But though they 

 are so, this in no way lessens the value of descriptions 

 and figures for the purpose of comparing different floras, 

 their distribution, the climatal conditions of each age, 

 and inferring the relative age of isolated remains of land 

 surfaces, volcanic outbursts, elevations, &c. It matters 

 less whether a widely spread leaf-form is referred to oak 

 or beech, than to ascertain that it is characteristic of a 

 definite age and had a definite distribution. Fortunately 

 there are palaeo-botanists like M. Lesquereux who, 

 having done their utmost to assign a leaf to its right 

 genus, are content to wait for certain proof until the 

 discovery of fruits and more perfect specimens. 



Among the more interesting plants described are a 

 Lycopodium and three species of Selaginella, all well 

 pfeserved. The discovery of these is remarkable, as M. 

 Lesquereux states that none of the Lycopodiaceae had 

 previously been known between Oolitic and recent times. 

 The ferns are also of especial interest. Besides Lygo- 

 dium and Pteris (which forcibly recall both Eocene and 

 Miocene European forms), we have in Gymnogramina 

 Hayde?iu, from the Lower Lignite, a form also common 

 at Bournemouth (now described from more perfect fronds 

 as an Anemia), and to the Aix-la-Chapelle flora as Asple- 

 niumForsteri, Deb. and Ett., and to Suzanne as Asplenium 

 subcretacetim, Saporta. Conifers and palms are nume- 

 rous, but being fragmentary are less easy to compare 

 Avith those of other localities. Still less so are other 

 Monocotyledons, except a single Miocene Sinilax leaf 

 identified with a European species. 



The Dicotyledons are very numerous, 212 species 

 being described. Of these the leaves ascribed to My- 

 rica, a large group mostly from the Upper or Miocene 

 series, have an Eocene aspect. The forms assigned to 

 Betula, Alnus, Carpinus, Cotylus, and Fa^us, are very 

 similar to each other, and appear, from the figures, to 

 have perhaps been too much subdivided. Any of these 

 might be identified with leaves from Bournemouth, where 

 the beds are undoubtedly Eocene. The leaf- forms from 

 the Lower Lignite described as oaks have been deter- 

 mined with considerable hesitation, and are of most dissi- 

 milar character, as we see indicated by such specific names 

 as 2. piatinia, Q. vibi^rni/olta, Q. negundioides. They 

 have been classed as oaks on account of greater or less 

 resemblance to species so described by European authors 

 holding very diverse views. The single Castanea is indis- 

 tinguishable from an Alum bay-leaf. In the simple forms of 

 the Saliciniae we have perhaps the nearest approach in cha- 

 racter to European forms, and a large proportion of them 

 will be found identical with leaves from Bournemouth. 

 We must not, however, attach undue importance to the 

 apparent similarity of simple ovate or lanceolate leaves 

 especially when comparisons are made from drawings 

 only. The poplars form a large group, but, considering 

 the variability of their leaves, species appear to have been 

 unnecessarily multiplied, some being determined from 

 fragments of leaves and others from single specimens, as 

 P. melanarioides, P. 7nelanaj'ia, &c. P. Zaddachi is a 

 familiar leaf in the English Bagshot and Woolwich beds, 

 and in the Arctic beds, so-called Miocene ; P. Richard- 

 soni also appears identical with this form. Leaves, 

 so similar to each other in outline and variation, that 



from the plates they can scarcely be distinguished, are 

 described respectively as Querctis platania, Popidus Icevi- 

 gata, and Platanus Raynoldsii and we long to know why 

 they are so distinctly separated. The only leaf ascribed 

 to Ubmcs is from the Miocene stage, but appears identical 

 with a Bournemouth form. Again Qucrcus acrodon, 

 Planera Uiige^'i and Fagus feronice could all be matched 

 with leaves from Bournemouth, and so resemble each 

 other that it appears strained to have separated them 

 under three genera and to form two new species from 

 such material. On the other hand, one of the five 

 figures (Fig. 5, pi. 28) ascribed to Ficus lanceolata is 

 quite distinct from the rest and is certainly not that 

 species, but a common British Eocene form. Ficiis 

 multinervis, Heer, is one of our most abundant Eocene 

 plants, and, as suggested by Saporta, is more probably a 

 Laurus. Leaves referred to Ficus oblanceolata, Lesq., 

 analogous to another of our species, might reasonably have 

 been separated as two species. As a group, the leaves 

 called Ficus remind us of those met with in the Eocene. 

 A remarkable feature in the flora is, that but a single 

 form is referred to the Proteacete, and from its cha- 

 racters it seems unnecessary to refer even this to that 

 group. Of the Lauriniae, Launis has an Eocene aspect, 

 whilst the species of Cinnamonum appear correctly iden- 

 tified with Miocene forms. The nine species of Vibtirnum, 

 which would perhaps have been better reduced to two, 

 are analogous to a Bournemouth leaf, but still more so to 

 the Viburnum of Suzanne. A leaf referred to the 

 Australian genus, Caliicoma, is of simple lanceolate form, 

 with serrated edge, whilst two other forms referred to 

 Ericacece are very indistinctly characterised. Many of 

 those named Sapindus and Diospyros, as well as Zizyphus 

 and Rhainttus, are of essentially Eocene facies and very 

 similar to Bournemouth forms. The leaves placed 

 together as Ilex dissimilis are so unlike that it seems 

 doubtful whether they could hare belonged to the same 

 species. 



The apparent defects which are here pointed out, may 

 be partly due to imperfect figures, and reference to the 

 specimens themselves might uphold the correctness of 

 M. Lesquereux's separate determinations, since the 

 specific identity or otherwise, of leaf forms, is often, after 

 all, very much a matter of individual opinion. 



The third part of the work contains a tabulated 

 list of all the plants with the relative position of 

 the beds from which they are derived, and also their 

 possible relationship to those of the Eocene and Miocene 

 strata of Europe. This is followed by a careful digest of 

 the matter contained in the work, from which the'follow- 

 ing important facts are to be gathered. The lower group 

 contains 200 out of the 325 species described, and is so 

 isolated that but sixteen of the forms pass into the higher 

 tertiaries, and these include none of the essential types, as 

 the palms, magnolias, Grewiopsis, Viburnum, Rhamnus, 

 &c. The second group has thirty-four species, twenty 

 peculiar to it, and is, on the whole, correlated rather with 

 the overlying Miocene than with the Lower Lignitic. 

 The third group is unhesitatingly pronounced to be 

 Middle Miocene, on account of the relation of its plants 

 to the so-called Miocenes of Alaska, Greenland, Spitz- 

 bergen, and Europe ; and it is further said that no Eocene 

 type is present in the group. The fourth group is also 



