572 SCIENCE PROGRESS 



Willis, B., The Discoidal Structure of the Lithosphere, Proc. Nat. Acad. 



Set., 1919, 5, 377- 8 3- 

 Barrell, J., The Nature and Bearings of Isostasy, Amer. Journ. Sci., 1919, 



48, 281-90 ; The Status of the Theory of Isostasy, ibid., 291-338. 

 Cox, A. H., A Report on Magnetic Disturbances in Northamptonshire and 



Leicestershire, and their Relation to the Geological Structure, Phil. 



Trans., Ser. A., 1919, 219, 73-135. 

 Bryan, K., The Classification of Springs, Journ. Geol., 1919, 27, 522-61. 

 Gregory, J. W., A Low-Level Glaciated Surface in the Eastern Himalaya, 



Geol. Mag., 1919, pp. 397-406. 

 Shaw, E. W., Present Tendencies in Geology — Sedimentation, Journ. 



Washington Acad. Sci., 19 19, 9, 513-21. 

 Kindle, E. M., Inequalities of Sedimentation, Journ. Geol., 1919, 27, 339-66. 

 Galloway, J. J., The Rounding of Grains of Sand by Solution, Amer. Journ. 



Sci., 1919, 47, 270-80. 

 Kindle, E. M., A Neglected Factor in the Rounding of Sand Grains, ibid., 



431-4- 

 Wentworth, C. K., A Laboratory and Field Study of Cobble Abrasion, 



Journ. Geol., 1919, 27, 507-21. 

 Giles, A. W., Brecciation in the Niagara Limestone at Rochester, New 



York, Amer. Journ. Sci., 1919, 47, 349~54- 

 Rastall, R. H., The Mineral Composition of the Lower Greensand Strata 



of Eastern England, Geol. Mag., 1919, pp. 211-20, 265-72. 



BOTANY. By E. J. Salisbury, D.Sc, F.L.S., University College, London. 



Anatomy and Cytology. — Several additional species of Mono- 

 cotyledons exhibiting intrafascicular cambium are recorded 

 by Mrs. Arber. These belong to the genera Juncus, Anigozan- 

 thos, Narcissus, Crocus, Iris, Morcea, Sisyrinchium, Carludovica, 

 and Sciaphila {Ann. Bot.). In the same journal Carter describes 

 the detailed structure of the chloroplasts in Chcetomorpha, 

 Cladophora, and Rhizoc Ionium. In all cases it appears that these 

 form a parietal film, more or less perforated, from which strands 

 pass inwards when the cell contents are abundant. 



Worsdell, in an extensive paper dealing with the medullary 

 phloem in the stems of the Compositae (Ann. Bot.), concludes 

 that here also this is a vestige of a system of medullary 

 bundles. These latter are regarded as having been retained in 

 the petioles of certain species such as Inula helenium and 

 Petasites officinalis. The feature is attributed to a geophytic 

 habit in the ancestors of the group. 



Morphology. — Several interesting papers dealing with the 

 marine algse have, during the past year, appeared in the Journal 

 of Botany from the pen of Dr. Church. These not only sum- 

 marise much of the scattered literature, but are also very 



