660 DR J. STARK ON SHEDDING OF BRANCHES AND LEAVES IN CON IFERA. 
some species, the juvenile characteristic is completely lost, the leaves being subsequently 
developed exclusively as phyllodia: in some, the original condition is completely retained ; 
while in others we have the intermediate condition, the plant, throughout life, producing both 
kinds of leaves. The case of the phyllodineous Acacias having when young the compound - 
leaves so characteristic of the order Leguminosz to which they belong, is one of those specially 
referred to by Mr Darwin “(Origin of Species,” 4th edition, p. 519), in illustration of what he 
terms “the law of embryonic resemblance,” expressing thereby the fact that in a given group 
the resemblance between the different forms is found to be greater the younger the stage or 
phase of development :—in other words, that the structure is more general in type in the 
younger stages, and more specialised in the older ones. 
Lastly, Dr Srark’s observation as to the ramules of Zhaja developing for the most part 
female cones the second season and male flowers the third season, is of interest as suggesting the 
existence of a condition (possibly not uncommon in the group to which the genus belongs), 
which is at once curiously like and curiously unlike that of Dichogamy, as seen in hermaphrodite 
flowers; for it is evident that in Thuja the female flowers of one generation of ramules would 
thus almost necessarily be fertilised by pollen from male flowers developed upon ramules of 
an older generation. 
EXPLANATION OF PLATE. 
The figures, about two-thirds of the natural size, are photo-lithographic reductions from “nature 
prints” of the fallen ramules. 
Thuja occidentalis (Common Arbor-vite). 
Figures 1, 2. Fallen ramules with the still adhering female cones of the second season; and the 
third season’s male catkins terminating most of the smaller twigs. 
Figures 3, 4, 5. Fallen ramules, showing numerous male catkins of the third season. 
Libocedrus decurrens. 
Figure 6. Fallen ramule. 
Cupressus (Chamecyparis) Lawsoniana. 
Figures 7, 8, 9. Fallen ramules. 
Cupressus (Chamecyparis) Nuth«ensis. 
Figures 10, 11. Fallen ramules. 
Juniperus Virginiana. 
Figure 12. Fallen ramule, exhibiting spreading needle-like foliage, like that of ordinary Junipers. 
Figures 13, 14. Fallen ramules, exhibiting appressed scale-like foliage, like that of Cypresses. 
Sequoia sempervirens (Californian Redwood). 
Figure 15. Fallen ramule of two season’s growth 
Figure 16. Do. dao. three do. do. 
Figure 17. Do. do. four do. do. 
Figure 18. Do. dao. five do. do. 
Figure 19. Fallen ramule of two seasons’ growth, and branched. 
Sequoia (Wellingtonia) gigantea. 
Figures 20, 21, 22. Fallen ramules. 

