*98 
THE FLORIST AND POMOLOGIST. 
numberless gradations ? It is looking for what nature has not done, and forcing 
her to enter into an artificial category. 
To whatever hypothesis we may lean, as regards the notion of a species, 
we cannot help seeing that it presents itself under different aspects, sometimes 
restricted within narrow limits, strictly characterised, and not varying sensibly, 
but sometimes also prodigiously broad, polymorphous, and, so to speak, divisible 
ad infinitum. Pear trees form no exception; and many other genera of plants 
offer the same profusion of secondary forms, and are an equal source of per¬ 
plexity to classifiers. 
Almost all pomologists, at least those who are worthy of the name, have 
tried to classify Pear trees; but all have failed, in so far, at least, as they have 
never been able, in consequence of the intermixture of characters, to make an 
arrangement in the least degree natural, and which would embrace all the 
known varieties. At the commencement of my studies, like my predecessors, 
I thought that I might undertake this work with some chance of success; now 
I am disabused of this hope, and I do not fear to declare that every classifica¬ 
tion will be purely artificial. The only useful principle which can be adopted 
here will be, I think, the time of the ripening of the fruit, because in an 
economical point of view this consideration predominates over all others ; and 
even here, again, we must assign very wide limits to these seasons of maturity. 
Neither the form of the fruit, nor their size, nor their colour, nor their 
flavour, any more than the habit and appearance of the trees, the colour of the 
wood, the size of the leaves and flowers, &c., can afford any base for a classi¬ 
fication, because all these characters are purely individual, which they do 
not transmit faithfully by way of generation, and, which, as there are not 
wanting examples to prove, change soon in one and the same individual in con¬ 
sequence of local circumstances which one cannot always explain. 
The partisans of the plurality of species may object, in the group of trees 
with which we are occupied, that if in this multitude of intermediate forms we 
are unable to recognise distinct specific types, this depends on the fact that the 
primitive species have intercrossed thousands of times ; and their fertile hybrids 
have increased in an enormous degree the number of crossed, and that from 
thence have sprung these innumerable forms which are the despair of classifiers. 
I am far from denying the fact of these crosses or of their influence ; I say 
even that nothing appears to me more probable; at least it is not possible to 
doubt it, when we see what takes place in a Pear orchard when in flower, 
where the bees, attracted from a distance of a league, pilfer from morning till 
evening, mingling the pollen of all the varieties, and disseminating it on 
stigmas for which it was not destined by nature. But we may remark that 
these impregnations, which are supposed to be unnatural, are always fruitful, 
that all the flowers which receive pollen from any kind of Pear whatsoever, set 
their ovary, and that the fruit when developed always contains fertile seed.* 
But, I ask, will this constant fertility, after all possible crosses, afford a 
proof of the difference of primitive types ? Precisely the contrary conclusion 
is suggested ; and when we have seen the same fact produced in other species, 
at the same time well characterised, and quite as polymorphous as the Pear 
tree, for example in the Potiron (Cucurbita maxima), the Pumpkin (C. pepo), 
* I know no apparent exception to this fertility, except in the Poires sails pepins and Comte de 
Flandre, whose fruit contains no seeds ; hut this does not prove a want of power in the pollen, which, 
besides, might as well be that of its own parent tree as of a tree of any other variety. In fact I have 
ascertained that this defect of seed depends, in the first of these varieties, on the more or less complete 
abortion of the ovaries, and in the second of an absolute want of ovules.—J. D. In Cucurbita mos- 
chata, the fruit of which, at least in the Courge pleine de Naples, closely resembles the Pear in many 
respects, there is sometimes a total abortion of ovaries, and the fruit beneath the rind consists merely 
of a mass of parenchymatous tissue.— Rev. M. J. Berkeley. 
