174 THE JOURNAL OF BOTANY 
special importance, sae sen! stand in opposition to the generally 
received opinion as to ecidental and often unstable existence 
of hybrid productions. Th e Mints answering to the form ulas 
rotundifolia-sylvestris and aquatica-arvensis behave to all appearance 
i o the extent of having deluded, and a in 
delusion, the vast majority of floristes with “regard to them. They 
seem to dustify Kunth’s ribbon allegory, but this.comparison n has its 
foundation only on a superficial examination of facts. In either 
ai 
settavee verify the double origin of intermediate forms, and the 
two specific unities, freed from the confusion that surrounds their 
wins appears perfectly clear 
he preservation of hybrids is favoured, in the Mints, by the 
mechanism of a powerful vegetative system which, by the help of 
layers and suckers, assures an almost ors Sa propagation of the 
plant ncaa oy: Ht oe sexual organs, which, especially in the 
males e ofte n not iumpentesity developed. The vege- 
tatiees of individual tee sually more vigorous than that of the 
ans — in certain cases as far as actually supplanting 
them. pone beca me Sra Baga if not even exclusive, in the 
ted. 
of investigation, when their utility is once better aes d, will be 
applied with success to other genuses— Rubus, Ros a, Hieracium, 
t is only then that the examination of cacti apparently 
insolvable, which these names will recall to the ‘botanist, can be 
resumed upon a new basis, and that at last the monte circle of 
fruitless discussions, within which the old methods confined them, 
will be broken. The most recent labours of learned monographers— 
for instance, — of M. Crépin on Rosa, and of M. Boulay on 
Rubus—tend more and more to strengthen this hypothesis 
There remains a word to say on a theory to which we alluded 
above. its ubstitutes for the facts of hybridization that we have 
established, imaginary phenomena of evolution. The intermediate 
c 
formation, springing of the old, but receding gradually by suc- 
cessive differentiations, whose last term, after the extinction of the 
middle stages, would end by realizing a definite type. This appli- 
nore in miniature of the Darwinian theo unts in reality 
to an avowal of inadequacy. The results of our ——— researches, 
rf toda by proofs, have already condemned it 
