March ii, 1886J 



NA TURE 



435 



ing the flora to partake far more of that of the 

 Pacific than of the Atlantic coast. It differs, however, 

 notably from the Cahfornian flora in the paucity of 

 Papaveracea;, Rhauinea;, Hydrophyllacea;, Labiata;, 

 CupuHfene, Coniferas, and Lihacea:. 



The distribution in the United States of America of the 

 4S0 indigenous European species,' which form an integral 

 part of their flora, offers some very interesting matters for 

 consideration. Of these there are indigenous to the 



Rocky Mountain Flora about 300 



Eastern United States „ 370 



Cahfornian „ 225 



Common to all „ 135 



The following list of some of the Rocky Mountain 

 species not found either in the Eastern Alps or Sierra 

 Nevada of California is a very instructive one. No doubt 

 some occur in the northern continuation of the Sierra 

 Nevada, in Oregon, and Washington, &c. ; such are there- 

 fore plants of the Pacific States, though not Cahfornian : — 

 Ranunculus hyperboreus, Ado.xa Moschatellina 



nivalis, pygmasus, and Hieracium umbellatum 



affinis Campanula uniflora 



Thalictrum alpinum Androsace Chamaejasme 



Papaver nudicaule Gentiana frigida, glacialis, 



Draba stellata, incana prostrata 



Viola biflora Swertia perennis 



Cerastium alpinum Lloydia serotina 



Sagina nivalis Juncus triglumis, castaneus 



Elatine triandra Kobresia caricina 



Astragalus hypoglottis Care.'i microglochin, rupes- 



Potentilla nivea tris, obtusata, frigida, am- 



Saxifraga Hirculus, flagel- pullacea, nardina, gyno- 



laris, ca;spitosa, cernua, crates, incurva, steno- 



adscendcns, punctata phylla, elongata, leporina 



Chrysosplenium alternifo- Alopecurus alpinus 



hum Deyeu.xia lapponica 



Epilobium latifolium Catabrosa aquatica 



These it will be seen are for the most part Arctic 

 plants, whose presence might be expected on any range 

 of mountains of sufficient elevation in America ; but they 

 are absent both in the Sierra Nevada and the White 

 Mountains of the Eastern States. On the other hand, it 

 is not easy to account for the absence in the Rocky 

 Mountains of an even greater number of European species 

 which are found in the Eastern States or in California, or 

 both, and of which some occur in most other meridians 

 of the globe. Such are especially 

 Caltha palustris Trientalis europasa 



Nuphar lutea Euphrasia officinalis 



Cardamine bellidifolia and Prunella vulgaris 



pratensis Armeria vulgaris 



Arabis petrasa Myrica Gale 



Drosera (all the 3 European Salix herbacea 



species) Betula alba 



Arenaria peploides Taxus baccata 



Montia fontana Rhynchospora alba and 



Oxalis Acetosella fusca 



Oxytropis campestris Carex (24 species, chiefly 



Rubus Chamaemorus boreal) 



CircKa lutetiana and alpina Tofieldia palustris 

 Lythrum Salicaria Narthecium ossifragum 



Lobelia Dortmanna Luzula arcuata 



Erices (12 species, nearly Hierochloe alpina 



all Arctic, and both Euro- Aira alropurpurea 



pean and Asiatic) Glyceria fluitans 



Menyanthes trifoliata 



^ In Gray's " Vegetation of the Rocky Mountain Region," cited above, 

 will be found an exhaustive table of comparison of all the Alpine plants of 

 the .Atlantic. Pacific, and Rocky Mountain regions as then known. Coulter's 

 " Flora," however, introduces considerable modifications in its details. 



Neither the climate of the Rocky Mountain region, 

 its elevation, its geological structure or its physical 

 features, appear to present obstacles to the migration into 

 it of these common plants of the colder north temperate 

 zone from Canada or from the Eastern United States. 

 It is still more difficult to understand how those that occur 

 in all three adjacent American regions should have become 

 excluded from the fourth, which they may be said to 

 bound. 



It remains to add that Dr. Coulter's manual is well got 

 up, and though claiming in the preface to be no more 

 than a compilation, it is really a very useful work. The 

 only important omission observed, and it is a very serious 

 one, is that of the elevations at which the plants grow. 

 It is a great advance on the fragmentary " Synopsis of 

 the Colorado Flora " by Porter and Coulter, which was 

 welcome in its day ; and though there is no doubt that a 

 good many more species will be found in a future edition, 

 and that some of the data extracted above will be thereby 

 interfered with, there is no reason to suppose that these 

 will clash with the main facts, which so amply confirm all 

 the conclusions that Asa Gray drew years ago from the 

 comparatively imperfect data then at his disposal. 



J. D. H. 



MORLEY'S ''ORGANIC CHEMISTRY" 



Outlines of Organic Chemistry. By H. Forster Morley, 



M.A., D.Sc. (London : J. and A. Churchill, 1S86.) 



THE faults into which the writer of a text-book ot 

 organic chemistry for students is apt to be led are, 

 as Dr. Morley points out in his preface, that of over- 

 elaboration on the one hand, to which the material too 

 readily lends itself, and that of unintelligent abridgment 

 on the other. Dr. Morley adopts a satisfactory com- 

 promise by selecting for treatment a relatively small 

 number of typical compounds, giving, however, " as much 

 consideration to each compound as it would receive in a 

 large treatise." Some departures from this rule are, as 

 he candidly confesses, due to the necessity of taking into 

 account "the requirements of students working for 

 examinations." 



Dr. Morley's arrangement of his subject is new — so far 

 at least as it has not been anticipated in Prof. Remsen's 

 " Organic Chemistry," which, however, did not appear 

 until after the completion of the present work in manu- 

 script. " I have endeavoured," he says, " to describe 

 compounds in the order in which they may be synthetic- 

 ally produced, so that each compound should be a 

 product of the one before and a producer of the one 

 after." We must confess to having doubts as to how far, 

 save in the interests of very young students, such an 

 entire sacrifice of the symmetry of the ordinary clas- 

 sification as is involved in this arrangement is judicious. 



Most text-books of organic chemistry contain, prefi.xed 

 to each class of compounds, preliminary chapters dealing 

 with the general modes of preparation, the properties and 

 the reactions of the entire class. This arrangement finds 

 no favour in the author's eyes. " Not until he (the 

 student) finds that a series of reactions can be grouped 

 together under some general expression should he be 

 allowed to mention a general law." The principle is 

 doubtless, within its proper limits, sound ; but we should 



