The Hunterian oration : Royal College of Surgeons of England, February 14th, 1895 / by J. W. Hulke.

  • Hulke, John Whitaker.
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: The Hunterian oration : Royal College of Surgeons of England, February 14th, 1895 / by J. W. Hulke. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    systole. Having defined irritability as the power of responding to stimuli by internal and external work, he calls attention to the visible movements of “ whole parts of plants,” as examples of this property. lie adduces the movements of the leaves of the legu- minous plant, the Hedysarum gyranSy as an instance of this phenomenon; and he comments on an appa- rent analogy between these movements and those of respiration in animals suggested by their periodic repetition in both divisions of organic nature. Here he is, however, careful to avoid the error of attribut- ing to these superficial resemblances an essential correspondence of function. With characteristic cau- tiousness he proceeds :—“ This [i. e. the recurring leaf-movement] is an action apparently similar to breathing in animals, though, perhaps, it does not answer the same purpose.’’ The circling movements of tendrils, as if seeking for a mechanical support, and their twining round this when they have come into contact with it, did not escape his notice. Neither did he overlook the remarkable circumstance which characterizes the twining of the stems of certain climbing plants, viz. its constant direction for each plant. He cites the Honeysuckle (Lonicera) and the Hop (Ilumnlus) as climbers, of both of which he says “their stems turn to the left; whereas the stem of Clitoria (a pea) and that of Convolvulus turn to the right.” He instances Dioncea Muscipula (Venus’s Fly-trap) and the Mimosa pudica (Sensitive Plant) as plants