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distant from each other; the whole connected by transverse veins, and 
in the fresh state often more than one-fourth of an inch in width, the 
whole appearing, until closely inspected, a compact solid midrib, on 
either side of which are two to five fine veins, the whole connected by 
numerous secondary veinlets. Some of the submerged leaves were 
eighteen inches in length, and most beautifully pellucid, in this 
respect far surpassing the other British members of the genus. The 
floating leaves were scarcely coriaceous, linear-lanceolate or lanceolate, 
and occurred only in small quantities. The original specimen, in 
Mr. Babington’s possession, exhibits traces of this peculiar midrib, 
which, I think, is almost sufficient to identify it with my specimen. 
The differences alluded to in the outset, are not more than may 
be found between specimens of well-known species gathered in‘ their 
prime, and others gathered, as in the present specimens, where decay 
has actually commenced, witness P. rufescens and P. zosterzefolius. 
In the last-named species, the early leaves are invariably apiculate, 
but no trace of an apiculus is to be found in those produced during or 
after flowering time. Whether the plant is identical with P. longi- 
folius, Gay, is a question I am not prepared to answer, but feel much 
disposed to doubt the latter being anything more than a name; 
at any rate no individual, with fresh specimens of my Lough Corrib 
plant before him, could overlook the prominent midrib, (although in 
the dried state it is not nearly so conspicuous). Mr. Babington, from 
inspection of some of my dried specimens, considers it different from 
his original specimen, on the grounds already stated, and is disposed 
to look upon it as, perhaps, Potamogeton sparganifolius, Fries. Mr. 
Borrer, to whom I sent recent fragments as well as dried specimens, 
considers it identical with the E. B.S. plant.” 
Mr. Moore, of Glasnevin, in transmitting similar specimens from 
Lough Corrib, named them P. longifolius. 
Specimens of the Potamogeton were exhibited from Mr. Kirk, as 
well as some other rare plants, such as Rosa Sabini, var. Doniana, 
Potamogeton flabellatus, Naias flexilis, Rubus infestus, W. et N., R. 
Balfourianus, Bloa., Symphytum tauricum, &c. 
Mr. M‘Nab communicated a register of the flowering of certain 
hardy plants in the Botanic Garden, as compared with the flowering 
of the same species during 1851 and 1853. 
Also read, ‘ Illustrations on the application of Nature Printing to 
the copying of Botanical Specimens ;’ by W. Lauder Lindsay, M.D. 
—— Ss ee 
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