The _Methodus Nova_ is something more than a system of classification. The systematic part of the work is preceded by five _Sectiones_ which are morphological essays bearing the following titles: I. _De Plantarum seminibus observationes quaedam generales_: II. _De Foliis Plantarum seminalibus dictis_: III. _De Plantula seminali reliquisque semine contentis_: IV. _De Floribus Plantarum, eorumque partibus et differentiis_: V. _De Divisione Plantarum generali in Arbores, Frutices, Suffrutices at Herbas_. Beginning with the last, it is a discussion of the propriety of retaining the old Theophrastian sub-divisions: Ray agreed with Jung (see p. 15) that they are popular rather than accurate and philosophical, but he retained them on the ground of expediency. The fourth _Sectio_ is an outline of the morphology of the flower based upon Jung's _Isagoge_ which Ray had received in MS. from Dr John Worthington who had obtained it from Samuel Hartlib, as is explained in the Preface. The first three _Sectiones_ are of peculiar interest: they give an account of Ray's observations upon seeds and seedlings, with quotations from Malpighi's recent work on the same subject (_Anatomes Plantarum_, _Pars Prima_, 1675; _Pars altera_, 1679), recognizing the fact that the seedlings of some plants have two seed-leaves or cotyledons (as Malpighi first called them), those of others only one, a fact which came to be of great systematic importance. The classification of the _Methodus Nova_ was maintained by Ray in his _Historia Plantarum_ (t. i, 1686), as well as in both the first (1690) and second (1696) editions of his _Synopsis Methodica Stirpium Britannicarum_, somewhat improved and more compact in form. His ultimate views were expressed in the _Methodus Plantarum emendata et aucta_, published in 1703 not long before his death. In many respects this final form of his system is a great improvement upon that of 1682; more especially in the adoption of the number of the seed-leaves as a systematic character. Ray, it is true, limited the application of this character to herbaceous plants, as he had not brought himself to give up the old categories of Herbs, Shrubs and Trees: nevertheless, he founded in this work the groups of _Dicotyledones_ and _Monocotyledones_ which persist, though materially altered as to their content, to the present day. =Ray's= _Methodus Emendata et Aucta_, 1703. DE HERBIS. =Flore Destitutae.= Genus i. Submarinae: Algae, &c. " ii. Fungi. " iii. Musci: Bryophyta with _Lycopodium_. " iv. Capillares: Filices. Herbae sui generis: _Ophioglossum_, _Pilularia_, _Salvinia_, _Salicornia_, &c. =Floriferae.= _Dicotyledones._