434 Proceedings of the 



from the calibre, presses upon the end of the mandrel with effect 

 proportioned to its surface. 



Some specimens of fulgorites, or the tubes formed in sandy soils 

 by lightning, from Westphalia, were laid upon the tables by Dr. 

 Fiedler, as also some large and rare minerals. The general na- 

 ture of the fulgorites was explained from the lecture table by Mr. 

 Faraday. 



May 30th. 



A discourse on the comparative anatomy and physiology of the 

 ear, was delivered in the lecture room by Mr. Curtis. 



Several fine pictures and engravings were exhibited in the library, 

 together with some curious autographs from the extensive collection 

 of Mr. Upcott. 



June 6tL 



Mr. Gilbert Burnett delivered a lecture on sensitive plants, of 

 which the following is an outline. 



Every individual of the vegetable kingdom is more or less en- 

 dowed with motility, as instanced by the raising, drooping, and 

 turning of their leaves to light, the opening and closing of their 

 flowers, &c. &c., which constitute the vigils and the sleep of plants ; 

 but, although these motions may be seen in all, in none are they 

 more notorious, perhaps in none more familiar than in the sensitive 

 or humble plants, from which motions the generic name Mimosa 

 has been derived. The M. sensitiva is very rare in Europe ; the 

 common sensitive plant of our hot-houses is the M. pudica. 



Some of the phenomena exhibited by these plants must have been 

 notorious as long as the plants have themselves been known, such 

 as the rising of the leaflets, the approach of the pinnules, and the 

 collapse of the leaves on the application of any undue stimulus ; 

 but these phenomena having been rather the subject of vulgar ad* 

 miration than of physiological research, at least Mr. Mayo and 

 myself not being aware of any, we agreed to institute a series of ex- 

 periments to explicate the matter ; but in the course of our inquiries, 

 we found that, in some of our experiments, we had been anticipated 

 by Dr. Dutrochet ; and having been led by a Slight notice in Smith's 

 Introduction to Botany, to consult a paper sent by Mr. Lindsay 

 from Jamaica, and read to the Royal Society, A.D. 1790, but not 

 published, we were surprised to find, that in the very experiments 

 in which we had been forestalled by Dutrochet, had Dutrochet been 



