Botanical Society of Edinburgh. 223 



BOTANICAL SOCIETY OF EDINBURGH. 



This Society met on Thursday, June 13th, at the Royal Botanic 

 Gardens, Professor Graham, President, in the chair. 



1. "On four genera of Desmidiece," by Mr. John Ralfs, Penzance. 

 The genera are Cosmariuin, Pediastrum, Xanthidium, and Scenedes- 

 mus, and the descriptions of them, which were accompanied by illus- 

 trative drawings, will shortly appear in the ' Annals and Magazine 

 of Natural History.' 



2. " Continuation of Mr. James M'Nab's Journal of a Tour through 

 part of the United States and the Canadas." In the previous part 

 of this Journal, Mr. M'Nab gave a brief outline of the principal 

 botanical and horticultural features observed in the neighbourhood 

 of New York. The part now read embraced chiefly the appearance 

 of the country around Albany, with an account of the most interest- 

 ing plants seen during the journey thither. Among these the most 

 remarkable were several species of Lycopodium, with which the 

 peaty soils on the road-sides around Albany were covered, consisting 

 of L. complunatum, clavatum and dcndroidcs, the latter resembling at 

 a distance young spruce firs, being similarly shaped and of a lively 

 green colour. In damp situations in the close forests, Adiantum 

 pedatum and other ferns covered large tracts, while Pyrola cllipiica 

 and rotiindifoUa, with Chemophylla maculata and umbellata, were in 

 full flower along the drier parts. Satyriimi herhiola and Neottia tor- 

 tilts were also observed, the latter growing chiefly in pairs. The 

 principal plants noticed in the meadows or open grounds were Lilium 

 philadelphicum and canadense, Mimulus ringens, Verbena hastata 

 and urticifolia, and Asclcpias ohtiisifoUa and variegata. Proceeding 

 towards Troy on the banks of the Hudson, great quantities of Kal- 

 mia angustifolia., Cornus fiorida, Lupinus perennis, Andromedas, Vac- 

 ciniums, &c. occurred. In an extensive forest, chiefly composed of 

 small trees, and much entangled with Smilax or green brier, through 

 which the party proceeded with great difficulty, Cypripedium specta- 

 bile covered large patches, with Arum triphyllum, the latter in full 

 flower. Mr. M'Nab concluded the present part of his Journal with 

 an account of some large trees of the hemlock spruce, Abies cana- 

 densis, being the first of this tree which the party had observed in 

 natural situations ; the largest specimens were about 10 feet in cir- 

 cumference and 80 feet in height. 



This Society held its last meeting for the session on Thursday 

 July 11th, at the Royal Botanic Garden, Professor Graham in the 

 chair. 



The Treasurer read a paper on three genera of Desmidiece, by 

 Mr. John Ralfs, Penzance, viz. Desmidium, Glcsoprium, and Schisto- 

 chilum, 



Mr. James M'Nab read a portion of his Journal of a Tour in the 

 United States and Canadas. In the last notice Mr. M'Nab gave an 

 account of the excursion from Albany to Troy, and thence to Still- 

 water, with notices of the most interesting plants observed during 

 the journey thither ; the present portion is chiefly confined to obser- 



