154 THE VICTORIAN NATURALIST. 



418 and 419. The peculiarity of this pretty orchid is the spon- 

 taneous periodic oscillation of the labellum. When I found this 

 plant at the beginning of the present month I noticed the labellum 

 displayed a peculiar motion. This reminded me of the habits 

 of Candollca, Leeuwenhoechia dubia, Brachycome calocarpa, whose 

 certain floral parts also display a strange mobility on being 

 touched ; but as the labellum repeated the oscillation, I watched 

 it closely, and observed that it happened in a precise space of 

 time. I have had the specimens for a week in a glass of water, 

 and observed them in various parts of the day, but always found 

 that no circumstance can be attributed to this singular action of 

 the labellum. The time elapsing between the oscillations varies 

 from ten to twelve minutes, during which time I tried the 

 labellum by jerking it, breathing on it, &c, to continue the 

 motion, but in vain. After the lapse of the said time a slight 

 quivering of the anterior base of the labellum might have been 

 seen, and then suddenly it would jerk, describe an arc of about 

 8o°, and remain in that position for the said time, after which the 

 motion would repeat itself. 



I have submitted this observation to Baron F. von Mueller, 

 K.C.M.G., &c, and that gentleman (to whom I owe all my 

 botanical knowledge) informs me he has noticed the jerking of 

 the labellum of Pterostylis mutica in 1848, and published it in 

 SchlechtendaFs "Linnsea" in 1853; but that he did not know 

 that the oscillation was spontaneous-periodic. He, therefore, 

 thinks that I am the first who has made this observation. 



He further says that R. Brown, who collected in Australia from 

 1802-1805, and founded the genus Pterostylis, did not mention 

 anything about this motion. Also, Billardiere, who also observed 

 a Tasmanian species, P. prcscox, of which he made drawings in 

 1806 as Disperis alata, and rendered a good description of its 

 form, never mentioned anything about the motion of the label- 

 lum. Fitzgerald, in his great special work on Australian orchids, 

 has taken notice of the jerking of the labellum, but not of a 

 spontaneous. In 1840 Ronald Gunn has noticed the irrita- 

 bility of the labellum of P. mutica, P. longifolia, P. nutans, 

 from notes in Lindley's " Genera and Species of Orchideous 

 Plants." Thanking you in anticipation, yours, 



G. P. ECKERT. 



Lutheran School, Minyip, 30th December, 1890. 



We have much pleasure in congratulating Professor M'Coy upon 

 the distinction lately conferred upon him by Her Majesty the 

 Queen. Sir Richard Owen, Sir Joseph Hooker, Sir William 

 Dawson, Sir James Hector, Sir William Macleay, and Sir Fer- 

 dinand von Mueller make up the list of living biological knights, 

 we believe, and it is matter of congratulation for the Field Club 

 that its two science patrons are amongst so limited a number. 



