In the intact plant, under favourable conditions, these movements are easily observed to take place more or less continuously; but there are times when they come to a standstill. For this reason and because of the fact that a large plant cannot easily be manipulated as a whole and subjected to various changing conditions which the purpose of the investigation demands, it is desirable, if possible, to experiment with the detached petiole, carrying the pulsating leaflet. The required amputation however may be followed by arrest of the pulsating movements. But, as in the case of the isolated heart in a state of standstill, Dr. Bose found that the movement of the leaflet can be renewed, in the detached specimen, by the application of the internal hydrostatic pressure. Under these conditions, the rhythmic pulsations are easily maintained uniform for several hours. This is a great advantage, in as much as in the undetached specimen, the pulsations are not usually found to be so regular as they now become. So small a specimen, again, can easily be subjected to changing experimental conditions, such as the variation of internal hydrostatic pressure and temperature, application of different drugs, vapours and gases. Under varying conditions the same plant has been observed to take different response times, as for instance, less in heat than in cold, less in summer than in winter, less in the morning than in the evening, and so forth. Again, different plants have different response times. It is a remarkable fact that the mimosa is ten times as sensitive as a frog in giving the response. And the native idea that plants are of a lower order than animal life will cost many a sad disappointment. In the course of his lecture Dr. Bose spoke of some of his startling discoveries recently made.... The lecturer gave quite a spiritual turn to his discourse as he finished it with the remark that, as it has been the earnest endeavour of scientists to minimise material friction in order to get the best results, so in our human concerns, it should be our best aim to minimise friction,--which is, Ignorance. --_Modern Review_, Vol. XII, pages 314-315. PLANT AUTOGRAPHS HOW PLANTS CAN RECORD THEIR OWN STORY Under the presidency of His Excellency Lord Carmichael, Prof. J. C. Bose delivered on Friday, the 17th January 1913 an interesting address on his recent researches at the Physical Laboratory of the Presidency College, Calcutta, his subject being "Plant Autographs."