SECTIONAL TRANSACTIONS.—K. 453 
12. Miss E. R. Saunpers.—On Some Anatomical and Physiological 
Relations in the Dicotyledon Shoot. 
The appearance of certain superficial anatomical characters exhibited by the 
seedlings and developed shoots of many Dicotyledons leads to the following 
conclusions : (1) that the Dicotyledon hypocotyl must be regarded as a com- 
pound structure consisting of an axial core clothed in a cotyledon skin; (2) that 
the epicotyl shoot is built up in the same manner, the vegetative axis being 
covered with the extended bases of the foliage leaves, the flower stalk with 
those of bracts or sepals. The view taken of the construction of the Dicotyledon 
shoot differs from the earlier conceptions of Hofmeister and Nageli and from 
the Pericaulom theory recently brought forward by Potonié in two respects. 
It is based neither upon evolutionary theory nor on paleontological argument, 
but is deduced from patent characters in the living plant. It is put forward 
only in regard to the most superficial layer (or layers) of the stem, since only 
here do we appear to have clear evidence of the existence of boundaries. 
13. Major C. C. Hurst.—Origin of the Moss Rose. 
Only differs from the old Cabbage Rose which has been cultivated in Europe 
more than 2,000 years in multiple branching of its gland structures ; nevertheless 
twelve authors gave it a specific rank. The sterility of the old Cabbage and 
old Moss Rose makes genetic investigation difficult, but bud variation of Moss 
and Cabbage Rose seems to throw light on their constitution, and if so gives a 
new value to bud mutation. 
14, Prof. R. C. McLnan.—On the Behaviour of the Somatic Nucleus in 
Development. 
Discovery of the binucleate phase in the developing soma cell. Ontogenetic 
origin of the condition. Evidence for subsequent reduction by fusion. Occur- 
rence of amitosis? Bearing of this process on somatic senescence, normal histo- 
genesis, and somatic segregation of characters. 
15. Prof. R. H. Yapp and Miss Una C. Suans.—The Water Content 
of Developing Leaves. 
16. Prof. R. H. Yarr and Miss Nora Boycorr.—On Cell Form and 
Size in Vicia Faba under Varying Conditions of Illumination. 
17. Prof. F. E. Werss.—Popular Lecture on Graft Hybrids. 
Tuesday, September 13. 
18. Joint Meeting with Sections A, C, and D. Discussion on The 
Age of the Earth. Seep. 413. 
19, Discussion on Size and Form. Prof. F. O. Bowsur, F.R.S., Prof. 
J. H. Priestuny, Dr. D. H. Scott, F.RB.S. 
20. Dr. J. P. Lorsy.—Factors of Evolution. 
To trace the course of evolution by the genealogy of species is erroneous. 
The species concept remains an abstraction; Nature consists of individuals ; 
similar individuals form syngameons, and these have been mistaken for species. 
As the gamete takes precedence over the individual, the course of evolution 
should be traced by the genealogy of the gametes. The fundamental question 
of evolution is: can a gamete vary by itself without loss of chromosomes, and 
are such variants transmissible? The only transmissible changes proved to 
occur are the results of crossing. These changes transgress the limits of 
Linnean species. The inheritance of cytoplasmic characters occurs in the 
female line only in the higher organisms, and is therefore not affected by 
crossing. Crosses between gametes having a differing number of chromosomes : 
triploids in @nothera and in the author’s own experiments. The hybrids of 
Papaver spp. and of microspecies of Vrophila. 
