PROCEEDINGS OF SOCIETIES. 



Dublin Mioeoscopical Club. 

 July 15fh, 1875. 



Leaf-Structure in Sphagnum Austini, Sullivant, and Sph. 

 papillosum, Lindberg. — Dr. Moore drew attention to the im- 

 portance of minute microscopic characters in the discrimination of 

 species, as exemplified in two related mosses, Sphagnum Austini, 

 Sullivant, and Sph. papillosum, Lindberg, and he exhibited speci- 

 mens of their leaves, pointing out the fringe-like marginal de- 

 velopment of processes around the spiral cells of the former, as 

 distinguished from the dot-like papillae occupying a similar 

 position in the latter. The former examples he had gathered 

 at the Island of Lewes. 



Differential characters found in the minute Structure of the 

 Leaves in Pinus Nordmanniana, P. pectinata, and another pro- 

 hahly new species. — Dr. McNab exhibited sections of the leaves 

 of three Pines, viz. Pinus (Abies) Nordmanniana, Pinus pecti- 

 nata, and a species from the Himalayas. The plant of the last is 

 growing in the Botanic Garden, Glasnevin, and was raised from 

 seeds received from the East India Company by Dr. Moore ; it 

 resembles P. pectinata in general appearance, but differs in the 

 shape of the leaf and in the quantity of hypoderm present. Pinus 

 pectinata differs from P. Nordmanniana in having the two resin- 

 canals in the parenchyma of the leaf, and not (as in P. Nord- 

 manniana) in contact with the inferior epidermis. The other form, 

 — which, if it turn out to be a new species, might be called Pinus 

 Mooreana — has the resin-canal in the parenchyma, as in P. pecti- 

 nata, but has a much-interrupted hypoderm, instead of the 

 almost continous layer met with in P. pectinata. 



Marasmis Hudsoni exhibited. — Mr. Gr. Pim showed Marasmis 

 Hudsoni, the long sharp bristles with which the pileus is beset 

 causing it to form a very pretty low-power object. 



Navicula divergens, form, exhibited. — Eev. E. O'Meara showed 

 a form of Navicula similar to N. divergens, but differing in being 

 regularly elliptical in outline. He had found this form occa- 

 sionally in the Lough Mourne deposit, and recently in great 

 abundance on a slide kindly supplied by Rev. George Davidson, 

 of Logie-Coldstone, the material having been gathered in a lake 

 in his neighbourhood, called Lough Canmore. 



