CONTENTS 



SECTION B.-BI()L()GICAL. GKOLOGIOAL, AND CHEMICAL 



SCIENCE. 



PAoa 



COLGAN (N.) : 



On the OcciuTence of Tropical Drift Seeds on the Irish Atlantic 



Coasts. (Plate X), 29 



Eakland (A.) : — 



See under Heron-Allen (E.) and A. Earland. 



Flood (Margaret G.), B.A. : — 



See under Henry (A.), M.A., and M. G. Flood. 



Halbert (J. N.) : — 



The Acarina of the Seashore. (Plates XXI-XXIII), . . .106 



Henry (A.), M.A., and M. G. Flood, B.A. :— 



The History of the London Plane. (Plates IV-IX), ... 9 



The History of the Dunkeld Hybrid Larch, Larix eurole/ns, with 



Notes on other Hybrid Conifers. (Plate XI), .... 65 

 The Douglas Firs : a Botanical and Silvicultural Description of the 



various Species of Pseudotsuga. (Plates XII-XIV), . . 67 



Heron-Allen (E.), F.R.S., and A. Earland: — 



An Experimental Study of the Foraminiferal Species Verneuilina 

 polystroplia (Reuss), and some others : being a contribution to a 

 discussion "On the Origin, Evolution, and Transmission of 

 Biological Characters." (Plates XVI-XVIII), .... 153 



Pbaeger (R. Lloyd), B.A. : — 



On Species of Sedum collected in China by L. H. Bailey in 1917. 



(Plates I-III), 1 



Stephens (Jane), B.A., B.Sc. ; — 



The Fresh-water Sponges of Ireland. (Plates XXVI-XXVIII), . 205 



Stephenson (T.A.), M.Sc. : — 



The Genus Corallimorphus. (Plates XIX-XX), . . . .178 



Wright (Mabel C.) :— 



Limnestheria : a New Conehostracan Genus from the Kilkenny Coal- 



Measures. (Plates XXIV-XXV) 187 



Wright (W. B.), B.A. :— 



Minor Periodicity in Glacial Retreat. (Plate XV), .... 93 



