Botanical Society of Edinburgh. 203 
from a single plant be reconciled with the phenomena, did, in the 
opinion of the author, furnish a demonstration of its absurdity. Dr. 
Hooker, while admitting the identity of the species of opposite hemi- 
spheres, acknowledging about thirty antarctic forms as identical with 
European plants, even after careful comparison and with the ablest 
coadjutors, is inclined to consider the identity, not as indicating a 
multitude of progenitors of a species, but as an anomaly, the ex- 
planation of which must be sought for ‘7m some natural cause.” 
Professor E. Forbes disposes of the anomaly in a more summary 
manner, by an assertion, that ‘“‘species of opposite hemispheres, 
placed under similar conditions, are representative, not identical.” 
If this opinion be correct, then form and structure are vastly inferior 
in value in the determination of species, to /atitude, a conclusion not 
likely to be adopted. ‘The author concluded by recommending the 
abolition of the term “specific centres of distribution,” a$ involving 
an erroneous hypothesis, and the substitution of the phrase ‘‘ patches 
of distribution.” 
Dr. Fleming exhibited a specimen of Xanthorrhea hastilis, which 
had been sent by Assistant-Commissary Neill from St. George’s 
Sound, together with some implements manufactured by the abori- 
gines, by means of the gum exuded from the bases of the leaves of 
this plant. 
July 12.—Dr. Balfour, President, in the Chair. 
re following papers were read :-— 
On Nostochinee,” by John Ralfs, Esq. “This paper comprised 
descriptions of species of Spherozyga and Cylindrospermum, and will 
appear in the ‘ Annals of Natural History’ and the Society’s ‘ Trans- 
actions.’ 
2. **On the Chemical Composition of the Fluid in the Ascidia of 
Nepenthes,” by Dr. A. Voelcker of Frankfort. (See p. 128.) 
Dr. Fleming called attention to the fact, that the young leaves of 
barley distil a clear fluid from their extremities. He was not aware 
of any analysis having been made of it. 
Dr. Balfour alluded to a similar phenomenon on the leaf of 
Richardia (Calla) Aithiopica; and Dr. Cleghorn made some remarks 
on the acid secretion (oxalic acid) of Cicer arietinum, the chick pea, 
which he had often observed the ryots collecting in India. 
3. “Notes of Excursions in the neighbourhood of Edinburgh,” by 
Dr. Balfour. In these notes Dr. Balfour gave a short account of the 
botanical trips which he had taken with his pupils this season to 
Daimahoy, Arniston, Dysart, Prestonhall, Melrose, Gullane, Queens- 
ferry and the Bass, and noticed some of the more interesting plants 
which had been gathered. 
4. Dr. Balfour exhibited specimens of roots which had entered 
and choked up tile-drains ; viz. of an ash which had penetrated tile- 
drains in Hampshire, filling them up completely for a great extent, 
and causing serious injury, and stated that similar occurrences had 
been observed in various parts of the country, more especially at 
Muirkirk, the Carse of Gowrie and Prestonhall. ‘The plants, whose 
