414 Pteridophyten. — Floristik etc. 



giving off of adventitious roots. The parallel banded type is regar- 

 ded as the deriviative form; it is developed in the ontogeny from the 

 radial banded type; the rearrangement of the bands at the point where 

 the one type passes into the other seems generally to occur at the 

 branehing of the stem, though it may occur elsewhere. Even in L. 

 Bülardieri, which has a stele of the radial banded type, the parallel 

 arrangement often makes its appearance at the ramification of the 

 smaller branches, but is immediately lost in the daughter branches; 

 a parallel rearrangement of the vascular tissues is not charaeteris- 

 tic of the main stem of this species. In L. volubile too, this paral- 

 lel disposition of the stelar tissue when initiated at a ramification 

 may be lost at once if the resulting branches are small. Generally 

 speaking where there are not more than five protoxylems there is 

 no parallel rearrangement of the dorsal part of the stelar tissue; 

 where there are from 6—9 protoxylems such a rearrangement is 

 frequent though not always much marked; in plants with more 

 numerous protoxylems a parallel banding of the dorsal part of the 

 stele is general. 



Finally the author agrees with Jones that radial and parallel 

 banded types are characteristic of orthotropic and plagiotropic stems 

 respectively. He also shows that heterophylly originated in a diffe- 

 rent way in L. volubile and L. scariosum. 



Isabel Browne (University College London). 



Lang, W. H., On the Stock of Isoetes. (Report British Assoc. 

 Section K. Sheffield, 1910.) 



The roots of Isoetes are, as von Mohl stated , borne in regulär 

 basipetal order on a region of the stele distinct from the first and 

 not on the secondarily modified base of the leaf bearing stem. The 

 root bearing portion appears to be strictly comparable to the Stig- 

 marian base of Lepidodendron and Pleuromeia. 



Isabel Browne (University College London). 



Maxon, W. R., Three new club-mosses from Panama. 

 (Smithsonian Miscellaneous Collections. LVI. N°. 23. p. 1—4. pl. 

 1 — 3. textfigure. January 6, 1912.) 



Three new species of Lycopodium are described from the high 

 mountains of western Panama: L. foliaceum Maxon, L. stamineum 

 Maxon and L. Watsonianum Maxon, all of the section Selago. All 

 are illustrated. Maxon. 



_______ 



Sargent, C. S. etal., PlantaeWilsonianae. An enumeration 

 ofthe woody plants collected in western China for the 

 Arnold Arboretum of Harvard University during the 

 vears 1907, 1908, and 1910 by E. H. Wilson. (Publ. Arnold 

 Arboretum No. 4, part II, p. 145—312, April 30, 1912.) 



Contains a critical treatment of several genera by eminent 

 specialists and includes the following new names: Deutsia pilosa var. 

 ochrophloes Rehder, D. cinerascens Rehder, D. Bodinieri Rehder, D. 

 lancifolia Rehder, D. crassifolia Rehder, D. crassifolia var. humilis 

 Rehder, D. Henryi Rehder, D. aspera Rehder, D. calycosa Rehder, 

 Hydrangea heteromalla var. mollis Rehder, Cotoneaster apiculata 

 Rehder and Wilson, C. nitens Rehder and Wilson, C. divaricata 



