vu 
Onagraceous Stem without Internodes, An [Plates II and Page 
III]—R. R. Gates . 50 
Origin of Species in the Genus Hieracium, Experiments 
on the (Apogamy and Hybridism)—C. H. Ostenfeld 347 
“ Osmosis, Nuclear ”—J. Bretland Farmer ... ... 139 
Osmotic Pressure in the Leaves of Non-Halophytes, On 
Induced Variations in the—Francis J. Lewis ... 255 
Pairing of Chromosomes, The—H. C. I. F(raser) (Mrs. 
Gwynne-Vaughan) ... ... ... ... ... 58 
Palaeobotany [Notes on Recent Literature]. S ee Psarouius 
and Glossopteris. 
Paleobotany, On Some Methods in—H. Hamshaw Thomas 109 
Pflanzengeographische Eindrucke auf den Britischen Inseln 
[International Phytogeographical Excursion in the 
British Isles, VII]—P. Graebner ... ... ... 170 
Phytogeographical Excursion in the Britsh Isles, see 
International. 
Plant Habitat, The Shingle Beach as a (Plate IV and 
8 Text-figs.)—F. W. Oliver ... ... ... ... 73 
Plasmatic Membrane and its Organisation, The—F. F. 
Blackman ... ... ... ... ... ... 180 
Polymorphism in the Flower of Silene maritima (Plate I 
and a Text-fig.)—E. J. Salisbury ... ... ... 7 
Promycelium of Coleosporium pulsatilhe Str., Notes on a 
Variation in the—James R. Weir ... ... ... 129 
Prothalli from the Lower Coal Measures, Two Fossil 
(Plates V and VI and 2 Text-figs.)—R. C. McLean 305 
Psarouius, Morphological Features in the Fossil Fern 
(with Text-fig.) [Notes on Recent Literature]— 
A. C. Seward ... ... ... ... ... ... 29 
Puccinia gram inis, The Wintering of [Notes on Recent 
Literature]—F. T. B(rooks)... ... ... ... 103 
Ray Tracheids in Sequoia sempervirens (7 Text-figs.)— 
Marjorie Gordon ... ... ... ... ... 1 
Recent Literature, Notes on :—See Alternation of 
Generations ; Angiosperms ; Bacteria; Bryophyta ; 
Genetic Factors ; Glossopteris; Heredity; Lichens; 
Meiosis ; Metabolism ; Psarouius ; Puccinia ; Rust 
Fungi; Scottish Botanical Review; Uredinales. 
Root to Stem, Theories of Anatomical Transition from 
(with Text-fig.)—R. H. Compton 
Rubiales. See Inferse. 
13 
