360 
OWER 
I propose on this occasion to treat of Median Prolification alone, reserving the axillary 
and lateral varieties for another opportunity. In Median Prolification the adventitious 
bud springs from the centre of the flower ; the usual arrest of growth which 
pot no longer holds good, hut a new growth takes place, manifesting itself generally 
formation of a new flower-bud, of a new leaf-bud, of a branch, or even in the pro 
duction of an inflorescence. The new growth may occur whether the carpels be present or 
not ; if present, then it may emerge from among or between them, or it may originate 
within the cavity of the carpels. 
Certain of the European families of plants (to which, with few exceptions, these remarks 
alone apply) present this deviation from their ordinary structure with greater frequency 
than others : thus the following orders seem to be the most frequently affected by it— Ra- 
nnnculace®, Caryophyllacece, Rosacea ; while it is commonly met with in Scrophularmcece, 
Rrimulacece, and JJmbelliferce. Of genera which seem peculiarly liable to it, I may men- 
tion the following— Anemone, Ranunculus, Cheiranthus, Dianthus, Dictamnus, Daucus, 
Rosa, Geum, Pyrus, Trifolium, Antirrhinum, Digitalis, Rrimula. Appended to this 
paper is a list showing the orders and genera in which prolification is recorded to have 
occurred, and specifying whether the new growth take the form of a flower-bud or of a 
leaf-bad ; the latter condition is, as Linnseus long since remarked, much less common 
than the former. The list must not be considered as complete ; but from the abundance 
of material at my disposal it may, I hope, be esteemed sufficiently so to illustrate and 
give colour to the remarks and opinions that I now venture to bring before the Society. 
A reference to the list of genera affected by this malformation, and the knowledge of its 
Comparatively greater frequency in some than in others of them, will show that it is moie 
often met with in plants having an indefinite form of inflorescence than in those havin 
a definite one. It would seem probable that there may be some real relation between 
the conditions ; but I am not prepared at present to affirm the existence of any thmg moi e 
than an apparent relation. 
The change may affect some only, or the whole of the flowers constituting an inflores- 
cence ; and though it is by no means a constant occurrence, it very frequently happens 
that the central or terminal flower in a definite inflorescence is alone affected, the otneis 
remaining in their ordinary condition, as in Pinks ; and in the indefinite forms ot inflo- 
rescence, it is equally common that the uppermost flower or flowers are the most liable 
0> 
be thus affected 
S 
In those plants which present this deviation from the ordinary condition with tne 
eatest frequency, it often happens that the axis is normally more or less prolongec , 
either between the various whorls of the flower, as in the case of the gynophore, etc., or into 
the cavity of the carpels, as in the instances of free central placentation. To bear out this 
assertion, I will cite the following instances taken from those genera having definite m- 
^^xxv^j-t* ""■ ' -*"o 
florescence, and which are very commonly affected with prolification : thus, in Anemone 
and Ranunculus the thalamus is prolonged to bear the numerous carpels ; in Dianthus 
there is a marked internode separating the carpels from the other parts of the flower ; m 
JPrimulacece central prolification is very common, and this is one of the orders where the 
placenta seems, from the researches of Duchartre and others, to be truly a production o 
