14 
are certain; besides these there are 29 which the author 
has not seen, and which are doubtless in some cases synonyms 
of others. 
A work more grateful than this to systematic botanists 
could hardly have been undertaken; for if there was one 
genus more difficult than another among Ferns it was cer- 
tainly Pteris. The author’s great object has been to elucidate 
the synonymy, and he appears to have done so with much 
skill and success, as may be seen from the result of his en- 
quiries into a few cases. P. angusta, elastica, and masca- 
renensis are the same as P. scabra; P. arguta, palustris, and 
lata belong to P. flabellata ; and, finally, P. discolor, glau- 
cescens, cruciata, sinuata, Lessoniana, and vespertilionis, and 
perhaps P. pallida, are referred to P. elegans. So that no 
fewer than sizteen are reduced to three. It is probable that 
few large genera exist, upon which numerous botanists have 
worked independently, in which similar reductions of species 
might not safely be made; and if so, what opinion is the 
statistical enquirer to form of the actual number of Vegetable 
species known to science ? 
FRUIT OF LEPTOTES BICOLOR, AROMATIC. 
Professor Morren has ascertained that the fruit of this 
pretty epiphyte, figured in the present work, vol. 19, t. 1625, 
is fragrant when ripe. By fertilizing it artificially, he suc- 
ceeded in twice obtaining its fruit, which he describes as re- 
sembling in smell the well-known Tonka or Tonquin bean of 
the perfumers; or the Sweet-vernal Grass (Anthoxanthum 
odoratum), which aromatises hay, only stronger and more 
penetrating than the last. It has been found that this fruit, 
infused in cream or milk, gives them, when iced, a mild 
agreeable flavour, sweeter than Vanilla but less penetrating. 
“ L'homme," adds the author, ** est avide de variétés dans sa 
nourriture; Part culinaire trouve ici un moyen de plus de 
contenter ses goüts capricieux, et Part du glacier de diminuer, 
chez ses produits, cet ennui qui, dit-on, naquit de l'uni- 
formitê.” 
ON THE MOTION OF GUM IN PLANTS. 
In his investigation of the anatomy of Cycadacee, Pro- 
fessor Morren has arrived at a fact of great interest in Vege- 
table physiology. It is well known that all these plants yield 
