144 



BRITISH ASSOCIATION FOR THE ADVAJSTCEMENT OF SCIENCE. 



[1855. 



class. Loch Skeen, Dumfriesshire, is formed by another such moraine, 

 the hills being 2,600 feet high, and the lake probably 1,200 feet. In 

 front of a similar recess to the westward are other lines and humps of 

 detritus ; but there is no lake, the water having escaped by a passage 

 still as clearly defined as a gate in a wall. A similar recess-moraine 

 occurs in the valley of Loch Ranza, Arran, 50 feet above the sea, a 

 furlong in length, with an opening in the centre ; the recess is occupied 

 by a morass. In the Lake district of England the author had obtained 

 additional evidence of glacial action in the Thirlmere valley, where it 

 enters the cross valley below the pass of Dummailraise, which connects 

 it with the Gtrasmere valley. There is a remarkable double ridge descend- 

 ing the hill side, about 30 feet high, its surface bristled with blocks, like 

 the train of detritus of a glacier 300 or 400 feet deep, coming down the 

 Thirlmere valley ; further down are other heaps of detritus along with 

 rounded and scratched rocks. The author's last observations on the 

 two sets of glacial phenomena were made at the Scotch mountain 

 Schiehallion, which rises from a base 1,100 feet above the sea to the 

 height of 3,600 feet, and is composed of quartz rock. It is abrupt to 

 the westward, and tails away to the east; the top of the ridge is 

 thickly strewn with loose slabs. About half-way up, and above the 

 level of Ferragon, the highest mountain to the eastward, there are 

 examples of sti-iated surfaces, and others within a few hundred feet of 

 the summit; the direction in both instances being W. 30 N., or the 

 same as that of the mountain ridge. About 800 feet below the summit 

 a block of granite was found, and other foreign blocks were noticed in 

 several places. These appearances, and the humps of brown moraine 

 detritus in the valley of the Tay, indicate sub-aerial glacial action; but 

 at the pass called White Bridge, the summit-level east of Schiehallion, 

 there is a deep bed of true boulder-clay with many worn and striated 

 blocks ; it lies out of the way of valley glaciers, and has escaped re- 

 moval by their agency. 



On Associations of Colour and Relations o<' Colour and Form in Plants: 

 by Du. G. Dickie. 

 The Professor remarked that relations in the form, structure, num- 

 ber and position of organs are familiar to every botanist : a priori it 

 mio-ht have been inferred, that order prevails also in the distribution 

 of colours. This is not only the fact ; there are, besides, obvious in- 

 dications of a relation between the colour and form of certain organs. 

 My attention was first directed to the subject in April, 1853, and the 

 facts here recorded were demonstrated to scientific friends at that date. 

 A brief account of the subject was communicated to the Belfast Natural 

 History Society in October following. Certain associations of colom- 

 have however, been known to artists who have cultivated the special 

 department of flower painting : any relation between form and colour 

 seems to have escaped notice, and even erroneous views have been 

 promulgated ; — for instance, by Ruskin in his ' Lamps of Architecture.' 

 The subject appears to have been very much — perhaps altogether — 

 overlooked by the botanist. The presence of all the colours, red, yel- 

 low blue, which form compound or white light, is a physical want of 

 the or^an of vision. Among the lower tribes of plants, the Algaa may 

 be mentioned as remai-kable examples of constantly associated colours. 

 Such, in fact, is the foundation of Prof. Haxwey's classification, who 

 divides them into red, green, and olive. Among the red there are 

 many which have a red-purple hue, and among the olive not a few 

 which are yellow-green stand in the same relation. Among mosses we 

 find the red or red-purple peristome associated with the green or yellow- 

 green capsule, and the same is true of their stems and leaves. In flower- 

 in" plants the associations of certain colours are so numerous, that it is 

 unnecessary in the summary to do more than mention a few examples. 

 In the leaves of Caladium pictum, C'oleus Blumei, and Victoria Regia 

 we find red or red-purple associated with green or yellow-green. The 

 same is true of the pitcher-like organs of Larracenise, Nepenthes, and 

 Dischidia. In the flower similar associations of various kinds are 

 common. We need not expect to find in a corolla or any other organ 

 the primaries red and yellow, or blue and red, associated and in con- 

 tact. The red has green, the yellow has purple, and the blue has 

 orange associated. Of the primaries, blue is rarest, — many cases so 

 denominated being, in fact, red-purples. In the flower yellow pre- 

 dominates, hence the very general difl:usion of purple of various degrees 

 of intensity. Purple being of such general occurrence in the flower, 

 we can now understand why yellow is the most common colour of pol- 

 len : some exceptional cases seem to confirm this ; in the turn-cap lily, 

 for example, the red pollen is associated with the green filaments. The 

 colour of the flower may have its complement in that of other parts, as 

 stem, leaf, &c. Sometimes the associated colours are not visible at the 

 same time. The inside of a ripe fig is red-purple, the outside yellow- 



green. Sometimes a yellow corolla is succeeded by a purple fruit. 

 Direct exposure to light, although usually and in general correctly 

 admitted to have a direct relation to intensity of colour in organisms, 

 appears not to be necessary in every instance. The plant, however, 

 must receive the light at some part or other, in order to produce that 

 intensity of colour observed in the coats of seeds, in the interior of 

 fruits, and in the tissues of subterranean organs. In conclusion — 1. 

 The primaries, red, yellow and blue, are generally to be seen in some 

 part of the plant. 2. When a primary occurs in any part of the plant. 

 its complement will usually be found in some other part, or at some 

 period or other of the development of the plant. I have found, in not 

 a few instances, in the animal kingdom similar associations of colour ; 

 birds, moUusca and radiata present many obvious examples. We may 

 next examine the relation between colour and form ; and the remarks 

 are, for the present, confined to the flower. Law 1. In regular poly- 

 petalous and gamopetalous corollsE the colour is uniformly distributed. 

 That is to say, the pieces of the corolla, being all uniform in size and 

 shape, have each an equal proportion of colour. Examples of this 

 occur in Primulacese, Boraginese, Ericacese, Gentianese, Papaveracese, 

 Cruciferse, Rosacese, Cactacese, &c. — Law 2. Irregularity of corolla is 

 associated with irregular distribution of colour. The odd lobe of the 

 corolla in such is most varied in form, size and colour. When there is 

 only colour, it is usually more intense in the odd lobe. When there 

 are two, one of them is very generally conflned to the odd lobe. Some- 

 times, when only one colour is present, and of uniform intensity in all 

 the pieces, the odd lobe has spots, or streaks, of white. The odd lobe, 

 therefore, in irregular flowers, is distinguished from the others not 

 merely by size, form, and position, but also by its colour. Papilionacese, 

 LabiatjB, Scrophularinese, &c., are examples. In some cases, as 

 Gloxinia, Achimenes, Rhododendron, &c., in which irrcgiUarity of 

 flower is less marked, the two pieces on each side of the odd lobe fre- 

 quently partake of its character as regards coloiir. In some thalami- 

 florous Exogens (as Pelargonium, Tropoeolum, jEsculus), &c., with ir- 

 regularity of flower, owing chiefly to diff'erence in the size of the pieces, 

 the largest are most highly coloured. — Law 3. Different forms of 

 corolla in the same inflorescence often present differences of colour, 

 but all of the same form have the same colour. The Compositse are 

 examples ; — when there are two colours, the flowers of the centre have 

 one colour and uniform in its intensity ; those of the circumference 

 also agree in this respect, but have the other colour. The first two 

 laws prevail in monocotyledons as well as in dicotyledons. In the 

 former the calyx and corolla generally resemble each other in structure, 

 shape, and in colour also. The law of the contrasts is, therefore, 

 simpler in monocotyledons than in dicotyledons. The former may be 

 symbolized by the triangle, three and six being the typical numbers 

 in the flower ; the latter by the square or pentagon, four and eight, 

 five or ten, being the prevalent numbers. Simplicity of figure corres- 

 ponds with simple contrast of colour in the one, while greater com- 

 plexity of colour and of structure are in direct relation in the other. 

 According to the investigations of Brongniart, there has been progres- 

 sive increase of angiospermous dicotyledons up to man's epoch. Among 

 them we find the floral organs with greater prominence in size, form 

 and colour, and such prominence of the "nuptial dress" of the plant 

 is peculiarly a feature of species belonging to natural families which 

 have found their maximum in man's epoch and are characteristic, 

 of it. 



Mr. Warrington gave an account of some experiments he had made 

 on the influence of coloured glass on the growth of plants in sea-water. 

 He found the red sea-plants grew best in glass-cases coloured green, 

 and that green Confervie were thus destroyed. — Mr. Huxley made some 

 remarks on the general theory of harmony and adaptation in nature. 

 He thought naturalists were too much disposed to take it for granted 

 that beauty was an end in creation. He believed, on the contrary, 

 that grotesqueness was frequently an object, and that inharmonious 

 and inapposite colours and forms were purposely brought together, and 

 thus excited the feeling of the ridiculous. — Dr. Carpenter called atten- 

 tion to the fact, that different chemical conditions of the plant produced 

 chemical colours ; and the point to be ascertained was whether these 

 were subservient to the laws of harmony sought to be established. 

 On the Progress of Naval Architecture and Steam Navigation, including 



a Notice of the Large Ship of the Eastern Steam Navigation Company,, 



by the President, Mr. Scott Russell. 



Mr. Russell explained the principles which guide the construction of 

 ships, and condemned the legislative restrictions which, till within the 

 last twenty years, prevented the application of those principles. The 

 old " sea chests," which were constructed with a view to avoid the taxa- 



