Scientific IntelligeTice.''^ Botany. 9&i 



and fewer. It is known that external temperature, by modify- 

 ing the progress of maturation, considerably influences the ab- 

 solute quantity of essential oil produced by the same vegetable. 

 The cold constitution of this year seems to have thus acted on 

 the phenomenon just described ; the utricles of the fraxinella 

 are smaller, and their inflammation appears less abundant, than 

 in the preceding years. — Dub. Journ.of Med. and Chem. Scien. 

 No. viii. p. 29. 



11. Influence of Colcmred Rays an the Growth of Plants. 

 By M. C. MoRREN. — In a paper which the author read to the 

 Academy about two years since, he had shewn that, of all the 

 elementary colours, those which are most favourable to the ma- 

 nifestation and development of organized beings, belonging 

 either to the animal or vegetable kingdom, are red and yellow, 

 and that this property exists in a nearly equal degree in each. 

 These, and other experiments, were verified at that time only in 

 the case of the most simple organized beings, in masses of water 

 subjected to the influence of the agents of the surrounding 

 world. M. Morren has tried whether the same results would 

 take place on making coloured rays act separately on earth in 

 which some grains were put to germinate. The experiments 

 were commenced on the 17th of March of this year. He took 

 nine pots filled with well dried earth, and of the same kind for 

 each, and in each pot he sowed twenty grains of cresses (Lepi^ 

 dium sativum). These seeds were then covered with a bed of 

 earth, three millimetres in depth. He sprinked each pot with 

 the same quantity of water from day to day. He covered each 

 with a tin vessel, blackened both inside and outside, twenty-two 

 centimetres in height, of a cylindrical form, one decimetre in 

 diameter, shut superiorly by a plate of tin, placed obliquely, and 

 inclined at an angle of 45°. Each plate was perforated in the 

 centre with a circular hole, before which was placed a circular 

 pane of glass, four centimetres in diameter, and differing in co- 

 lour for each vessel. These pieces of glass were such as are 

 used in ornamenting the old windows of churches, and were all 

 of the most beautiful tint : they were of the following colours, 

 — violet, blue, grass-green (vert pre), sea-green, bright yellow, 

 yellow, orange, red, purple. By the side of these vessels he 

 placed another vessel, black, such as themselves, but with a 

 white plate of glass. No ray passed through the solder, and care 



