242 Varietäten, Descendenz, Hybriden. — Physiologie. 
affect mountain tops and places in the southwestern forests. Every 
isolated mountain top has some. This being so, one must sup- 
pose that they have been evolved by mutation rather than by natural 
selection of infinitesimal variations, and this would also explain why 
most of them are so rare, the mutations not having proved speci- 
ally useful, and why they affect mountain tops, the conditions being 
there perhaps sufficiently different to cause a tendency towards 
mutation. In general they have characters which are, so far as one 
can conceive, useless in the struggle for existence; they occur in 
places where that struggle cannot have been very keen, or between 
very large numbers; they offen occur alongside of their most nearly 
allied species and very offen the differences in character are such 
as can hardly conceivably have arisen by the selection of infinite¬ 
simal variations. 
A closely similar state of things was revealed by a study of the 
floras of Mauritius and New Zealand. 
“The general principle on which India and Ceylon have been 
peopled with the many species which they contain would seem to 
be that one very common species has spread widely, and, so to 
speak, shed local endemic species at different points, or eise that 
one species has spread, changing at almost every point into a local 
endemic species, which has again changed on reaching new localities.” 
R. H. Lock. 
Jorissen, A., La linamarine, glucoside generateur d’acide 
cyanhydrique. Reponse ä la Note de M.M. Dunstan et 
Henry. (Bull, de l’Acad. roy. de Belgique (Classe des Sciences), 
N°. 7. p. 793—798. 1907.) 
L’auteur rappelle qu’en 1903 Dunstan et Henry se sont ab- 
stenus de faire la moindre allusion ä ses recherches, effectuees en 
collaboration avec Hairs, sur la linamarine, recherches qui remon- 
taient ä 1891. En 1906, Dunstan, Henry et Auld publierent leur 
memoire intitule: The occurence of phaseolunatin in common 
Flax, oü ils reproduisent et confirment les observations de Jorissen 
et Hairs sur le glucoside de Linum usitatissimum , mais oü il pro- 
posent de substituer la denomination de phaseolunatine ä celle de 
linamarine. Au contraire, A. Jorissen tient ä ce que cette denomi¬ 
nation de linamarine soit maintenue ä raison d’une Serie de notes 
publiees sur la diffusion de l’acide cyanhydrique dans le regne ve- 
getal il y a plus de vingt ans, et parce que, le premier, avec 
Hairs, il a retire d’un vegetal, et ä l’etat cristallin, un glucoside 
generateur d’acide cyanhydrique absolument distinct de l’amygda- 
line. A. Jorissen ne peut partager l’appreciation de Dunstan et 
Henry au sujet du peu d’importance de la nomenclature. D’apres 
une tradition justifiee, la denomination sous laquelle on designe un 
compose nouveau est celle qui a ete donnee ä ce compose par le 
chimiste qui, le premier, a isole le produit en question. Quinze ans 
avant Dunstan et Henry, A. Jorissen et E. Hairs ont decrit la 
preparation du glucoside du Lin et en ont isole une notable quantite 
ä l’etat de cristaux parfaitement blancs dont ils ont indique la com- 
position 61ementaire et le point de fusion. A cette epoque, ils n’ont 
pas fait l’etude complete de ce glucoside, mais il en a ete de meme 
pour Robiquet et Boutron-Charlard lorsqu’ils ont decouvert 
l’amygdaline. Certaines proprietes de cette substance sont encore 
discutees, et cependant il n’a pas ete question de denommer ce glu- 
