44 siti REPORT—1845. 
Onthe Specifie Characters of Plants, considered in Morphological Connewion. 
By J. Bart, M.RIA. 
Bearing in mind the two fundamental principles of the unity of primitive structure 
throughout all the organs of vegetation, and on the other hand, the connexion be- 
tween function and structure, as the latter is actually modified in nature, it has ever 
appeared to me a highly probable if not necessary conclusion, that where, in exami- 
ning a group of vegetable forms, we find in proceeding from one individual to another 
differences of structure in various organs, these varieties are mutually connected to- 
gether by fixed laws, so that a variation in one organ shall invariably accompany the 
variation of another, not by a mere accidental relation, but one which we may hope 
to trace and to establish. The main difficulty of introducing into botany this method, 
which has been so successfully employed in comparative anatomy by paleontologists, 
is, that the latter have been guided and directed by a knowledge of the functions of the 
seyeral organs whose’ structural relations they would discover, while in botany, where 
we have so slight a knowledge of the special functions of the various appendages, we 
must, if we would at all ascertain their structural relations, seek them in a careful induc- 
tion from an extensive series of observations ; thus only may we hope to reconstruct a - 
lost plant from some single leaf or portion of its inflorescence. The first step will na- 
turally be made in finding the relations between those organs in which the primary 
function has been the least altered, as between the leaf, the bracts, sepals or corolla, 
rather than with those of the stamens or pericarp, where the primitive organ has been 
altogether metamorphosed for the purpose of fulfilling a completely different purpose 
in the vegetable economy. Accordingly we do in fact find in many natural orders 
examples of this law. I might derive some illustrations from the Composite, but for 
the present shall only refer to a small group of Graminez, the whole of which order 
is well-adapted for this purpose. 
The group in question contains three European species of Polypogon, namely, 
P, monspeliensis, Dsf,, P, maritimus, R. & S,, and P. subspathaceus, Lois., in which the 
accordance between the variations of the leaf with unrolled sheath and those of the 
exterior glume is very remarkable. 
On the Geographical Distribution of Plants in British India 
By Dr, Royuz. : 
This paper contained an outline of the varied vegetation of India, occupying, as it 
does, almost the extremes of heat and cold, as well as those of dryness and moisture, 
The materials of this paper were chiefly supplied from the author's own observations. 
The number of species in India he estimated at 10,000, belonging to 200 families. 
The latter part of the paper was occupied with a description of the vegetation of the 
lakes. Plants are in them excessively abundant, and eventually fill them up with 
their debris. The author thought that the deposits of vegetable matter in these lakes 
threw much light on the formation of coal. 
Notes on the Irish Species of Robertsonian Sazifrages. 
By Professor ANDREWS. 
_ The author having studied the Irish Saxifrages, and compared them with those of 
the Pyrenees, had come to a different conclusion from Mr, Babington, and believed 
that there were only two true species in Jreland, the Saxifraga umbrosa and the S. 
Geum, ‘The other species described by Mr, Babington in his ‘ Manual,’ he regarded 
as varieties of one or other of these forms, ’ 
Capt, L. L, Y. S. Ibbetson exhibited a collection of electrotyped plants. Most of 
the specimens belonged to the family Orchidaceae, but there were many specimens of 
other plants, and some fungi, with their forms beautifully preserved. 
The process by which they were prepared was the ordinary electrotyping process ; 
but various expedients were had recourse to, according to the nature of the plant. 
Some difficulty was experienced in sinking the plant in the solution of copper. This 
was always least in plants which were brought from hot-houses. The parts of the 
plants on the surface were perfectly preserved, and many of them retained their 
specific characters, 
