November 24, 1923] 



NA TURE 



77 y 



the year, and soft cuttings, among which he dis- 

 tinguishes again between truly soft herbaceous plants, 

 such as the geranium, and the " lirmwood " cutting 

 of a shrub such as Escallonia. For firmwood cuttings 

 he agrees with the practice of using a side shoot, torn 

 from the parent stem with a downward pull so that 

 a little " heel " of the main stem is left attached to it. 

 Such " heeled " cuttings are described as almost 

 invariably easy to strike. Fuchsia, on the other 

 hand, strikes better if a piece of stem is cut off just 

 below a node, rather than from a side shoot broken 

 off with a " heel " ; clematis again, for some puzzling 

 reason, always roots best if cut about an inch below 

 a node. The author points out that the layering 

 method so frequently adopted with carnations is 

 also very successful with rhododendrons, hardy 

 azaleas, and other hardy shrubs. 



Assimilating Tissue in the Plant. — As first part 

 of vol. iv. of the Handbuch der Pflangenanatomie, 

 edited by K. Linsbauer (Berlin : Gebriider Bom- 

 traeger, 1923), there has appeared a review of the 

 assimilating tissues by Fritz Jiirgen Meyer. A full 

 bibliography and index appears with the review. The 

 various forms of assimilating tissue are fully de- 

 scribed, palisade and spongy tissue, arm palisade, 

 assimilating epidermis and bundle-sheath, etc., and a 

 resume given of the various views as to the develop- 

 ment from special assimilating tissues. The con- 

 clusion seems to be that we have not yet escaped 

 from a somewhat barren controversy as to the relative 

 importance of alternative teleological explanations 

 based upon its assumed functional activity. The 

 main protagonists have been Stahl and Haberlandt. 

 Stahl argued that the palisade system was the ideal 

 system for strong light, the spongy for weak light, 

 hence the relative proportions of these tissues in sun 

 and shade leaves. That light exerts an important 

 influence is supported by the recent experiments of 

 r.iese, which show the walls of the palisade cells 

 adopting a different angle when developing in a 

 radiation that comes in different directions. Haber- 

 landt, on the other hand, developed as explanatory 

 principles two adaptational requirements — (i) an in- 

 crease of cell surface, his main clue to the structure 

 of palisade and arm-palisade tissue ; (2) an increase 

 of length in the direction along which assimilates 

 move in the cell, an important guide to the inter- 

 pretation of spongy parenchyma. Other authors, 

 notably Areschoug and Rywosch, have argued stoutly 

 for the importance of transpiration and the moisture 

 conditions of the leaf, finding various reasons why 

 different types of tissue are best suited to certain 

 moisture conditions. All these views are usefully and 

 critically reviewed in this monograph. 



Indian Agricultural Statistics. — The agri- 

 cultural statistics of India for the year 1920-21 have 

 been published in two volumes by the Department of 

 "tatistics, Calcutta ; the first volume deals with 



ritish India and the second with certain Indian 

 states. Among a mass of valuable returns dealing 

 with acreage cultivated, areas under irrigation, extent 

 of different crops and live-stocks, and harvest prices, 

 it may he noted that the total area sown with crops in 

 British India in 1920-21 was 5 per cent, less than the 

 previous year, and represented 34 per cent, of the 

 total land area. Owing to the fact that some areas 

 are sown more than once in the year, the gross sown 

 area really amounts to rather more than this figure. 

 In the native states the sown area was about 40 per 

 cent, of the total land area. Food crops accounted 

 for 82 and 77 per cent, respectively of these two 

 totals. The irrigated area in British India remained 

 practically constant, while in the native states there 



^o. 2821, VOL. 1 12] 



was a slight increase. The area under cotton showed 

 a decrease of 9 per cent., and the area under oil seeds, 

 2 per cent. The rainfall was above normal in Bengal 

 and Assam and much of Burma, defective in the 

 United Provinces, Rajputana, and Bombay, and 

 especially so in the Punjab, Sind, and Central India, 

 but excessive in Madras. 



' Australian Notonectid^ . — The Australian water- 

 bugs of the family Notonectidae form the subject of 

 a contribution by Mr. Herbert M. Hale to the Records 

 of the South Australian Museum, vol. ii. No. 3, June 

 1923. The predominant genus is Anisops, which has 

 eight species ; nothing previously appears to have 

 been known concerning its life-history. Mr. Hale has 

 been able to fill this gap to some extent in describing 

 the biology and metamorphoses of the commonest 

 species, A. hyperion, which occurs in both running 

 and stagnant water. It was reared upon mosquito 

 larvae and pupae, which were eagerly devoured, an 

 average of 200 being consumed by each isolated 

 nymph in less than four weeks. Among other genera, 

 Notonecta and Plea are each represented by a single 

 species and there is but one member of the family 

 Corixidae — Porocorixa hirtifrons. 



Recent Shells from Java. — This first instalment 

 of what promises to be an important catalogue of the 

 " Recent Shells from Java " contains an enumeration 

 of the Gastropoda by Dr. C. H. Oostingh. The work, 

 written in English, is founded on a collection, chiefly 

 of marine shells from Java, which is kept in the 

 Geological Museum of the Agricultural High School at 

 Wageningen (Holland), and of this by far the greater 

 part was made by Prof. J. van Baren. An exact 

 knowledge of the recent moUuscan fauna being of 

 much importance for the study of the Upper Tertiary 

 fauna of Java, the author has approached the subject 

 in some detail. That is to say, a copious synonymy, 

 and notes of its distribution in the western Pacific 

 generally, with geological occurrences where known, 

 are given with each species, while there is a very good 

 phototype plate of some of the forms. 



The Glaciation of North-eastern Ireland. — 

 Major A. R. Dwerryhouse contributes a remarkable 

 paper. on this subject to the Quarterly Journal of the 

 Geological Society of London, vol. 79, p. 352 (Sept. 

 1923). The area covered is a wide one, from Tort 

 Head to Slieve Gallion, thence across the wild moor- 

 land of central Tyrone ; then away to the east coast 

 again across Lough Neagh, and down to the narrow 

 inlet of Carlingford Lough. The author recognises 

 this inlet as a true fjord excavated by glacier-ice 

 during the later phase, when the ice-flow from the 

 north-west dominated that from the Irish Sea. Good 

 use is made of the presence of pebbles from Ailsa 

 Craig in inland districts, and the course of the Scottish 

 ice (Firth of Clyde glacier) across the country during 

 the earlier phase is strikingly shown upon tne maps 

 (p. 419, etc.). The careful work of years is embodied 

 in this paper of seventy pages, and we can only regret 

 that space has not allowed of the description of the 

 picturesque scenic features added by clrift-mounds 

 and eskers to the floors of valleys or the barren surface 

 of the moors. Special attention is paid to the gravel- 

 terraces deposited in ice-dammed lakes, and to the 

 dry gaps as records of overflow-channels throughout 

 the district. It is pointed out that the recognition 

 of the true nature of these channels in north-eastern 

 Ireland dates from the work of the Geological Survey 

 in 1904. Here, as elsewhere in Ireland, Mr. G. W. 

 Lamplugh laid the foundations of a very marked 

 advance. 



