652 DR JAMES STARK ON THE SHEDDING OF 
and the cicatrix presented much the appearance which the horse-shoe mark 
does in the bark of the Horse-chestnut when the large leaf drops from the 
branch. The other branches were removed without a knife by merely bending 
down the branch so as to break the quill of woody fibre, when the branches fell 
off, leaving the bark cicatrised, or healed. 
The above incident set me a thinking. The mode in which these branches 
had been prepared to be thrown off, and the apparent provision of an articula- 
tion between the branch and the main stem, seemingly so analogous in general 
mechanism to that by which leaves drop off, excited my interest, and led me to 
examine, more closely than I had hitherto done, the defoliation in Conifere, 
and that process which, in Cupressines especially, often replaces it, viz., the 
shedding bodily of leafy twigs. 
In the following remarks I shall, in the first place, refer to members of the 
sub-order Cupressineze, in which I have examined plants belonging to six genera, 
viz., Thuja, Libocedrus, Cupressus, Juniperus, Sequoia, and W ellingtonia, in all of 
which “cladoptosis” occurs. I shall then turn to the sub-order Abietinee, 
commencing with the genus Pinus, where, in the periodic shedding of the stunted 
shoots bearing the leaf-fascicles, we are reminded of the analogous phenomenon 
in Cupressineze; and concluding with remarks on the defoliation, &c. of the 
genera Abies, Araucaria, Laria, and Cedrus. 
The deciduous leafy twigs may be designated as ramuli decidui; but, for 
shortness’ sake, I shall speak of them as ramules. 
Sub-Order CUPRESSINEA. 
Thuja occidentalis (Common Arbor-vitz).—Here the ramules are cast off 
annually, and may be collected in great quantities under old trees in September 
and October. Every one must recognise the fallen ramule, for it is the first thing 
which falls in the autumn and litters the shrubbery. In this species, the ramule 
generally remains for three seasons on the tree before it is dropped. During 
the jirst year, it is developed from a bud, and forms a central stem with short 
lateral secondary shoots. During the second year, these lateral shoots become 
compound from the formation of tentiary ones; and, if the plant is in flowering 
condition, the extremities of a variable number of the secondary and tertiary 
axes become developed as female cones; male flowers appearing only exce- 
tionally the second season. During the third year, the extremities of a large 
number, sometimes nearly the whole of the remaining branches, become deve- 
loped as male flowers or catkins; and, at the close of the season, the ramule 
drops off bodily, generally at the end of September or beginning of October, the 
exact time depending on the season. 
This is the general succession of events with the deciduous ramules; but 

