636 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
that occurs also in several other natural orders. The cause of this 
peculiar position is the setting up of an intercalary growth between the 
inflorescence and the supporting leaf. 
Multiple Buds.* — From a large series of observations M. W. Russell 
has arrived at the following conclusions on this subject. 
Lateral buds may be produced at the expense of the constituent 
parts of the leaf-axil, or at the expense of one part only, and that either 
the stem, or less often the leaf. They may make their appearance 
at the growing apex at the same time as their supporting leaf. Every 
bud at the beginning goes through a double growth ; there is, in 
fact, a growth of its own, and a growth in common with the organs 
which have formed it. The latter is generally stronger than the 
former, at all events at first ; and in consequence various coalescences 
are formed, and the apparent insertion of the bud is often carried 
much above its real insertion. The greater number of leaf-buds and 
numerous flower-buds are capable of putting forth ramifications from 
their base, at a time when they themselves are scarcely developed. 
These buds are the origin of a number of successive ramifications 
which accompany the bud of the first generation, and which are fre- 
quently without supporting leaves proper. These successive ramifica- 
tions, commonly described by the terms accessory buds of the axillary 
bud, or multiple buds, behave, from the point of view of their mode of 
formation, like the axillary bud itself. Hence, as in the case of the 
latter, there is a constant connection between the appearance of one 
of them and the number of leaves of the bud from which it springs. 
Similarly, if the bud of the first generation is coalescent with the axis, 
its ramifications are coalescent with each other. 
The arrangement of these buds always follows the laws of phyllo- 
taxis, even when they have no supporting leaf ; the function of pro- 
tection is in that case filled by the supporting leaf of the bud of the 
first generation forming round them, by its base or by its stipules, an 
envelope, which is often persistent. These basilar ramifications have a 
well-defined biological office. On them depends the ramification of the 
plants when the axillary bud is transformed into a spine, a tendril, or 
an inflorescence, or is destroyed accidentally or normally. In a great 
number of cases these buds remain in the state of dormant buds, and 
are the origin of the vigorous branches which appear under various 
circumstances on woody plants. Sometimes they play the part of 
hibernating buds, enabling the plants to vegetate from one year to 
the other. Finally, they can develope, in the year of their formation, 
or in the following year, at the same time as the bud of the first 
generation ; they then tend to render the ramification more bushy. 
It may be shown experimentally that the appearance of these buds 
may frequently continue during the entire life of the plant ; it is thus 
that, if a flower-bud of Convolvulus , for example, be suppressed, its basilar 
ramification takes the characteristics of a flower-bud. If this latter be 
taken away, a flowering branch of the third generation will make its 
appearance, followed later on by one of the fourth generation, and so on. 
Identical results may be obtained in most woody or herbaceous plants, 
by suppressing successively several generations of flower-buds. 
* Ann. Sci. Nat. (Bot.), xv. (1892) pp. 95-202 (4 pis.). 
