160 
Transactions of the 
[Monthly Microscopical 
Journal, March 1, 1869. 
botanical works as irregular metamorphoses. Such deviations from 
the normal structure, however, are not so irregular as might be 
supposed ; they are, on the contrary, constant in certain genera and 
species, and are found as certainly on the same branch as the normal 
structure itself. If a compound metamorphosed leaf be carefully 
examined, it will be found that the change implied consists in the 
apparent union of two or more of the leaflets into one lobed leaf, 
the rest of the leaflets remaining free, separate, or uncombined, on 
the same leaf. A quinate leaf, for instance, shall present us with 
the curious anomaly of two of its lateral leaflets joined into one, 
thus converting the leaf into one perfect lobed leaf on one side, 
and three separate leaflets on the other. Plate Y., D. Or, again, 
the two lateral leaflets on both sides shall have contracted union, 
forming a single compound leaf, consisting of two perfect bilobed 
leaves and a terminal separate leaflet. In another variety of the 
same species, a compound ternate leaf has all its leaflets joined into 
one trilobed leaf, and so on. I find analogous metamorphoses in 
Jasminum officinale, Buhus Idseus, Rhus tyjohina, Samhucus nigra, 
Rosa canina, Phaseolus multiflorus, Pastinaca sativa, Dahlia, 
Lycosjpermum esculentum, Angelica sylvestris, Berheris fortunii, 
Clematis montana. 
What is worthy of especial note, however, is the exact resem- 
blance in every minute particular borne by these united leaflets to 
the simple lobed leaf, whether in the normal venation in those parts 
of the leaflets which remain free, or in the modified venation where 
they have become united. In order more fully to exemplify this, 
let us revert to the leaf of the Blackberry, and examine a little 
more attentively the changes which have taken place in its venation 
in those leaflets which have coalesced into one from metamorphosis. 
The variety chosen is that which has five distinct separate feather- 
veined leaflets, radiating from the end of a common petiole, and 
constituting the true quinate compound leaf 
In its normal form all the leaflets are separate, and this is the 
type which prevails ; but I have never yet examined a specimen 
without finding several exceptions, — one compound leaf shall have 
five leaflets, a second four, a third three, all on the same branch. 
A little closer inspection shows, however, that this variation in the 
number of the leaflets is apparent, not real, for in each leaf five 
leaflets can be traced distinctly enough, emanating as from a common 
source from the stalk, each having its particular outline and vena- 
tion, only that two or more of them have become united at their 
edges, converting two leaflets into one, and so a quinate into a 
quaternate or ternate leaf. To leaves thus constituted, the adjec- 
tives fissus, partitus, can scarcely, I conceive, with propriety be 
applied. They owe their existence to the coalescence of two leaflets 
into one ; and although they may be said to be hilohed, they cannot 
