1 899-] Proceedings of Iiish Societies. 21 



November 17. — The Club met at Leinster House. 



Mr. Henry J. Seymour showed a specimen of the mineral Thorite 

 from near Arendal, Norway. The mineral contains about 60 per cent, of 

 Thorium, and forms the chief source of supply of this element, which is 

 largely used in the manufacture of incandescent gas mantles. The 

 specimen was given to him by a mining engineer who brought it, with 

 a number of other minerals, from the same locality, to Mr. Seymour for 

 identification. 



Prof. T. Johnson showed a preparation of Cladostephus verticillatus, a 

 common brown seaweed. The specimen was of interest in that it 

 showed the transition from the clothed summer sterile to the naked 

 winter fertile state. A branchlet of a sorus showed both unilocular and 

 plurilocular sporangia. 



Mr. Greenwood Pim exhibited Phragmidium (Aregma) tonncntilhc, 

 found at Ovoca during the visit of the British Mycological Society, and 

 an addition to the Irish flora. This fungus is very distinct from Phrag- 

 midium obtusatum, which occurs on another plant, Potentilla fragiriastium, 

 while P. tormentillcB occurs on Potentilla tormentilla. 



Canon RUSSEEI, exhibited sections of the petiole of the leaf of Rhu s 

 typhina at the point of junction with the stem, showing the partial 

 inclosure of the bud within the swollen base of the petiole. The bud 

 appears to be really axillary ; but, as Professor Miall, to whom Canon 

 Russell sent some specimens, observes, " over-arched to a singular 

 extent by the old petiole. The narrow air passage, as shown in the 

 section, is defended by a crowd of hairs which would be an effective 

 protection against the entry of water." The cavity in which the bud is 

 formed is also fringed with hairs, which, by the time the leaf falls off, 

 completely envelopes the bud itself as a winter covering. Professor 

 Miall" states that he sees that there is every degree of inclusion from 

 buds which are not sheltered at all to those of the Rhus typhina, which 

 is an extreme case of protection. He says— "The buds of Robinia 

 pseudaeacia are borne upon the scar usually flanked by two spines, They 

 are so effectively protected they are rather hard to see." 



Mr. M'Ardee exhibited Venturia bryophila, Fuuck, Sacc. Syll. Fung, 

 vol. i., page 395, a curious fungus which he found on the leaves of 

 Scapania czquiloba, one of the Hepaticae which he collected at Anniscaul, 

 Co. Kerry, in 1894-98. The perithicia are minute, of a dull brown colour, 

 beset with stiff bristles arranged on the ostiolum, not unlike the spokes 

 of a wheel. Asci minute clavate, eight-spored in two rows, spores 

 elliptic, oblong, uniseptate, hyaline. Paraphyses none. 



This species, which was identified by Mr. Massee, of the Kew 

 Herbarium, is a native of Germany and France, and has not been 

 reported previously in Great Britain or Ireland. Saccardo, in his grand 

 work, places it in the section with those which are found on Monocoty- 

 ledons and Acotyledons, and add that it is found in above-mentioned 

 countries on the leaves of [linger mania, Po'ytrichum, and Diphyscium. 



