564 Notices of Memoirs— GeohgisU^ Association — 



cellular plants which formed the only vegetation of the pre-Devonian 

 periods. No doubt there is in the older Palaeozoic rocks a great 

 absence of any records of land life. But the evolution of the vascu- 

 lar cryptogams and the phanerogams from the green seaweeds, 

 through the liverworts and mosses, if it took place, must have been 

 carried on through a long succession of ages and by an innumerable 

 series of gradually advancing steps ; and yet we find not a single 

 trace either of early water forms or later and necessarily still more 

 numerous dry land forms which should represent these intermediate 

 forms. This cannot be due to the physical conditions connected 

 with the preservation -of organic remains, for the conditions that 

 permitted the preservation of the Fucoid in the Llandovery rocks at 

 Malvern, and of similar cellular organisms elsewhere, were at least 

 favourable to the preservation of such plants as these must have 

 been if they ever existed. 



Mr. Carruthers then entered on the consideration of the higher or 

 dicotyledonous division of flowering plants. Their testimony for or 

 against the theory of evolution is the more important, because — 

 "first, of their higher organization, by which, as regards their vegeta- 

 tive organs, they are sharply separated from the monocotyledons, 

 and as regards both vegetative and reproductive organs from the 

 ;gymnosperms ; secondly, from the existence of numerous difierences 

 which supply generally obvious and well-defined characters for their 

 systematic classification, and which would consequently assist in 

 following the steps of their evolution ; and thirdly, from their appear- 

 ance in strata of comparatively recent age, and which are consequently 

 much better known than the Palseozoic deposits. Dicotjdedons are 

 usually divided into three groups — Ajpetalce, Ilonopetalce, and Foly- 



After a resume of Haeckel's scheme of the phylogeny of these 

 .groups, Mr. Carruthers proceeded : Now let us see what is the record 

 preserved to us in the rocks. Dicotyledonous plants make their ap- 

 pearance in strata which are referred to the Upper Cretaceous series. 

 No trace of these plants has yet been detected in any earlier stratum. 

 There is no j)al9eontological foundation for the suggestion that the 

 ApetaJcB existed in the Trias and Jura periods. It is difficult to 

 realize that the absence of dicotyledons can be due to any cause 

 but their absence from the then existing vegetation. The conditions 

 favourable to the preservation of Ferns, gymnosperms and monocoty- 

 ledons, in the Secondary rocks, must have been favourable also to the 

 preservation of dicotyledonous plants. Not only are dicotyledons 

 entirely absent, but there has not been discovered a single specimen 

 of a gymnosperm or monocotyledon which exhibits in any point of 

 its structure a modification towards the more highly-organized dico- 

 tyledon. Further, when the dicotyledons appear in the Upper Creta- 

 ceous beds, representatives of 'the three great divisions are found 

 together in the same deposit. Moreover, these divisions are not 

 represented by generalized tj'pes, but by differentiated forms which, 

 during the intervening epochs, have not developed even into higher 

 generic groups. Thus, amongst the AjpetalcB the MyricacecB are 

 represented in the Cretaceous rocks by two congeners of our bog- 



