December, 1911. 



KNOWLEDGE. 



479 



Cruciferous flower is fundamentally arranged in twos — that it 

 is dimerous — and that the four petals and the four inner 

 stamens are due to branching. This explanation has been 

 widely accepted. 



However. Klein (Bot. Cciiiralblatt, Band 58, 1894) has 

 urged that the Cruciferous flower is tetramerous — that is, 

 primarily arranged in fours, not in twos. He bases this ex- 

 planation chiefly on the position .and course of the vascular 

 bundles which supply the flower parts. Just below the flower 

 itself, the flower-stalU shows eight bundles arranged in an 

 ellipse. The first bundles to come off are at the ends of the 

 long axis of the ellipse, and they go into the two transversely- 

 placed sepals (though these are usually regarded as being the 

 outer and first-formed sepals): the bundles for the two median 

 (front and back) sepals come oft" higher up. Then, proceeding 

 upwards, come four strands which proceed diagonally (answer- 

 ing to the position of the four petals! ; each of these strands 

 soon branches into three veins, of which the median and 

 thickest one enters a petal, while the slender lateral ones go 

 into the neighbouring sepals — each sepal has, therefore, three 

 basal \eins (a thick middle vein and two slender lateral 

 veins). The veins for the two short stamens come oft' next ; 

 then four more veins running in the diagonal direction and 

 supplying the four long stamens. 



From the arrangement of these veins, or vascular bundles, 

 Klein concludes that the long inner stamens are diagonal in 

 position, but have become approximated in pairs lying in the 

 median (back and front) line, simply on account of the 

 exigencies of space in the developing flower, due especially to 

 the position of the nectaries. Klein, therefore, opposes the view 

 that the four inner stamens have arisen by branching from two 

 primordia situated in the median plane. Further up, there are 

 two laterally placed veins, right and left, corresponding to the 

 position of the two chambers of the ovary ; and last of all 

 come two veins lying in the median plane, which run up into 

 the partition of the ovary. Klein regards these veins as 

 belonging to two carpels which cannot develop owing to 

 exigencies of space. Hence Klein considers that the flower 

 parts are arranged in fours, with the theoretical formula K4. 

 C4, A4 4- 4, G (4). The outer whorl of stamens is incomplete 

 on account of the development of nectaries in place of two of 

 the stamens ; the inner four stamens are arranged diagonally, 

 being opposite the petals ; and the two fully-developed carpels 

 alternate with two abortive carpels. 



In further support of Klein's view, it may be mentioned that 

 in some Crucifers the four inner stamens are obviously diagonal, 

 rather than arranged in two pairs (anterior and posteriori ; also 

 that four carpels are present in genera like Hulargidiniit 

 and Tetraponuz. also in forms of Capsella. and in various 

 cultivated and wild varieties of other genera. 



CHEMISTRY. 



By C. AixswoRTH Mitchell. B.A. (Oxox.), F.I.C. 



A STALAGMITIC GROWTH IN SEA WATER.— An 

 interesting case of the formation of mineral growths of a 

 stalagmitic nature is described by Mr. T. Walton, in the current 

 issue of the Joiini. Soc. Clieiu. hid. (1911. XXX. 1198). 

 These were produced in an iron tank through which sea water 

 had been flowing for several months for the purpose of cooling 

 ammonia heated by pressure in a refrigerator. At several 

 points in the pipe there were minute leaks, and the passage of 

 the ammonia through these caused precipitation of some of the 

 lime and magnesia in the sea water, and from the nucleus thus 

 deposited upon the surface of the coil small columns of white 

 mineral matter had gradually risen to the surface of the water. 

 These formations ranged in length from five to fourteen inches, 

 and from a quarter of an inch to three inches in diameter. 

 Examined under the microscope they were seen to ha\e a 

 cellular structure, which was due to the pressure of the 

 escaping bubbles of ammonia gas. The dried material 

 composing these " stalagmites "' consisted of eighty-eight per 

 cent, of magnesium hydroxide, eight per cent, of calcium 

 carbonate, 0-9 per cent, of calcium sulphate, and 2-S per cent, 

 of sodimn chloride. 



ESTIMATION OF THE AGE OF BLOOD STAINS.— 

 .\ method of estimating the approxhnate age of blood stains 

 has been based by Dr. de Dominicis iBoll. Cliiiii. Farm., 

 1911, L, 273) upon the rate at which they may be dissolved. 

 A small portion of the stain. il is immersed in pure 



glycerine, and the tube given j . ^hake at intervals of a 



minute until solution occurs. The yeiiow solution is protected 

 from the air and compared with solutions obtained in the 

 same way from blood stains of known age, the relationship 

 between the colour of which and the time required for the 

 solution is also known. It was found that blood stains which 

 dissohed within one minute were undoubtedly of recent origin, 

 while the longer the solution period the older the stain. The 

 presence of blood in the solution should, of course, be proved 

 by means of the spectroscope. 



GEOLOGY. 



By G. W. TVKRELL. A.R.C.Sc, F.G.S. 



THE NEW GLASGOW MEMOIR.— In continuation of 

 the admirable policy of publishing maps and memoirs iflustrat- 

 ing the geology of large centres of population, the Geological 

 Survey has just issued a memoir and map of the Glasgow 

 district. These have been specially prepared, as we are told in the 

 preface, for economic and educational purposes with Glasgow 

 as the centre of interest. An official description of this 

 district was long overdue, for the old map (Sheet 30, 

 Scotland), published in 1878, was not accomp.anied by a 

 memoir. 



As a centre for extraordinarily interesting and varied 

 geology, Glasgow is perhaps unrivalled in the British Islands. 

 Standing in a basin of Coal Measures and Carboniferous 

 Limestone which is highly fossiliferous and replete with 

 stratigraphical problems, it is surrounded, at a distance of 

 a few miles, by an almost continuous rim of high volcanic 

 hills, built up of igneous material of great variety and 

 petrographical interest. To the north, at a distance of twenty 

 miles, are the Highlands — an area of m\-ster\- likely to provide 

 Glasgow geologists w^ith work for many \-ears to come. To 

 the west the Clyde lochs and islands, including .Arran — that 

 favoured isle of perennial petrological interest — are easy of 

 access. Also within an easy distance is the comparatively 

 untouched area of Ayrshire, full of new material awaiting the 

 geologist's hammer. 



Under these circumstances the new memoir is very welcome, 

 as providing a most valuable guide and groundwork to the 

 geolog>- of the district. The stratigraphical groups present in 

 the area described range from Lower Old Red Sandstone to the 

 Upper Barren Red Measures overlying the Coal Measures of 

 Lanarkshire. In Calciferous Sandstone times a great volcanic 

 episode occurred, w-hich gave rise to the fine terraced lava 

 escarpments of the Campsie and Kilpatrick Hills, flanked by 

 numerous isolated, conical, volcanic recks. Towards the end 

 of the Carboniferous period an interesting suite of teschenites 

 was intruded into the Coal Measures of the east of Glasgow. 

 Other rare igneous types are described, notably a bekinkinite 

 from Barshaw.near Paisley; and a beautiful porphyritic essexite 

 (long ago described by Allport) from Leimoxtown, both carrying 

 conspicuous nepheline. A good nepheline phonolite has also 

 been found near Fintry. The district is " full of petrographical 

 material of the first importance," says Mr. E. B. Bailey, who 

 has written the petrographical chapter ; and we concur with 

 his further remark that " the petrographical interest is likely 

 to quicken rather than flag as the igneous rocks of Ayrshire to 

 the west come to be examined." 



A meritorious feature is the long chapter on economic 

 geology, giving information as to coals, ironstones, fireclays, 

 limestones and cements, setts and road-metal, building stones, 

 brick-making and water supply, a list which illustrates the 

 extent to which geology is a practical and applied science. 



The colour-printed map is not so satisfactory as the memoir. 

 It is extremely complicated, and looks as if colour-printing 

 were being made to sustain an elaboration of detail of which 

 it is not capable. 



