^1^ BOTANICAL GAZETTE [February 



A new term, "helicomorphy," is suggested to comprehend Goebel's two 

 terms for the two leaf forms in heteroblastic species, the juvenile forms and 

 successive forms. In the course of a short chapter on the phylogenetic 

 significance of helicomorphy, the author pays his respects to the famous ** bioge- 

 netic law/' that ontogeny recapitulates phylogeny, in these terms: "In the botani- 

 cal field it has absolutely no (nicht einmal immer) heuristic value, and w^hoever 

 allows hmiself to be led by it will at most succeed in satisfying the needs of his 

 imagination." 



The book is one to be commended to all sorts of botanists; morphologists, 

 physiologists, ecologists, and taxonomists will alike profit by its perusal.— C. R. B. 



NOTES FOR STUDENTS 



Soil chemics and plant distribution.— Of late the physical character of the 

 soil, and especially the relation of the soil to water, has been more and more 

 regarded as the greatest single factor that determines plant distribution. For 

 this reason the contribution of Fernalds will come to most with something of a 

 shock. Fernald feels that the dissimilarity of the floras of the alpine districts 

 of Xew England and adjoining regions cannot be explained by differences in pre- 

 cipitation, exposure, fineness or coarseness of the soil, or water content of the 

 soil. On the other hand, it is possible to divide the alpine regions into three 

 groups on the basis of similar floras. The striking thing that then appears is that 



can 



nature of the subjacent rocks. One group, including the Adirondacks, Green 

 Mountains, l\liite Mountains, and Mt. Katahdin, is characterized by granites, 

 gneisses, or mica schists, all rich in potassium. The second group, including 

 Smuggler's Notch, Mt. Willoughby, and the Gaspe coast, is characterized by 

 calcareous rocks. The third group includes only the one remarkable area of Mt. 

 Albert, where many plants are found that are known from nowhere else in that 

 part of the continent; this area is one of serpentine. It will thus be seen that 

 Fernau)*s groups correspond to those made long ago in Europe by partisans of 

 tire chemical theor>', except that the European sHicicole group is replaced by 

 Fernald^s potassium group. It is likely that in a complex world not ever> thing 

 IS to be referred to one cause, and perhaps we have been too ready to see in soil 



answer 

 an excellent purpo: 



bered that this n-^ 



If so, Ferxald's paper will serve 



Yet it must be remem- 



and chemical factors can be adequately analyzed in the field. The trend of recent 

 experimental woii is mostly toward physical theories or toxic phases of chemical 

 theories,^ and until Fernald^s theories are substantiated by rigid experimental 

 tests, it is doubtful if they can find acceptance. It is well also to call attention to 

 the idea expressed so long ago by DeCanboixe in this connection, that what holds 



3 TERNALD. 



Rhodora o:u_& 



