58 PROCEEDINGS OF SOCIETIES. 



short-styled form is always considerably larger than that of the long- 

 stj'led. — " On Apothecia occurring in some Scytonematous and^Sirosi- 

 phonaceous Algae in addition to those previously known." By W. 

 Archer, M.R.I. A. According to Schwendener and others, Scytone- 

 matous and Sirosiphonaceous Algte form " gonidia " in two distinct 

 ways. They are either found in certain lichens as accidentally de- 

 tached fragments wholly involved by the hyphae in the substance of 

 the lichen-thallus, or they exist as perfect plants of their type, quite 

 unaltered in outward configuration, but permeated along the length 

 of the filaments by the hyphae which run between the rows of green 

 cells. It is from this that Schwendener argues the impossibility of 

 the genetic relationship of the hyphae and the young apical gonidia, 

 since these latter are formed before the arrival at the apex of the hyphal 

 filaments. The author has detected apothecia in two species of Scijto- 

 nema (one S. myochrous)^ in two species of Sirosiphoii (one S. alpinus) 

 and in Stigonema majnillosujn. He was, however, unable to detect 

 the presence of hyphae after many trials by boiling in caustic potash. 

 The examination was possibly not conducted sufficiently long or care- 

 fully, since the hyphae can be seen in Ephehe without boiling in potash, 

 and Bornet has shown their presence in Spilonema paradoxum and 

 Licheno splicer ia Lenormandi. [The paper is printed i7i extenso in 

 the '* Quart. Journ. Micr. Sc," for January, 1875, pp. 27 — 37, with 

 pi. iii.] 



Aug. 25. Department of Zoology and Botany. — Dr. Williams, 

 F.R.S., exhibited a series of finely-preserved specimens of marine alga3 

 from Jersey. — '' Comparative rates of growth in stems of Tree-ferns." 

 By Dr. Moore, Director Botanic Gardens, Glasnevin. It is generally 

 believed that the rate of growth of Tree-ferns is very slow. But this 

 appears to be by no means confirmed in the case of the species culti- 

 vated at Glasnevin. In 1855 Prof. Harvey sent home from one of the 

 Polynesian islands spores of a fern closely allied to Cyathea medul- 

 lar is^ — C. Mertensiana, Bong. ; a plant raised from these spores 

 reached a height of 1 feet in seventeen years. A plant of Alsophila 

 excelsa, from Australia, received at Glasnevin in 1850, had no woody 

 stem, and the fronds only about a foot long ; it has now a stem 12 

 feet high. A plant of Dicksonia antarctica was about 8 inches high in 

 1840, including fronds ; now it has a thick stem fully 5 feet high. 

 Some arborescent ferns form short rhizomatous stems, before they take 

 an upright position ; they require a considerable number of years to 

 perfect the early part of their growth, but after the stem has been 

 formed, and an upright position taken, the growth is much quicker 

 and the elongation advances rather rapidly, compared with what it 

 did while the stem remained in a rhizomatous state. — *' On structural 

 peculiarities of the Ampelidea.^^ By Prof. M. A. Lawson. The 

 general habit of the species was described. Reference was also made 

 to the large ducts in the wood, which become filled up by out-growths 

 from adjoining cells. The remarkable variation in the characters 

 afforded by the seeds was also pointed out. The author compared the 

 inflorescence in the remarkable genus Fterisanthes to that of Vitis sup- 



♦ A specimen of Cyathea mcduUaris doubled its height in eight years, and 

 ■was then 20 feet high. — Hooker's " Garden Ferns," tab. 25. 



