ii 



CONTENTS. 



VII. Account of some of the Rarer Plants observed du- 

 ring an Excursion in the United States and the 

 Canadas in 1834. Communicated by Mr James 

 Macnab, . . . . 56 



VIII. Remarks on the question, Does the observation made 

 in Coal-mines of Canada and of Baffin's Bay, of 

 plants analogous to those which live at present in 

 equatorial regions, announce a change in the in- 

 clination of the Ecliptic? By M. Marcel de 

 Serres, ... 64 



IX. Account of the Founding of a New Grand Observa- 

 tory for the Russian Empire, by the Imperial 

 Academy of Sciences of St Petersburgh, . 71 



X. Account of some remarkable Hailstones which fell 

 at Padua, on the 26th of August 1834. By D. 

 L. Cosari, 83 

 Hailstones of a Flattened and Irregular Shape, . . 84 



Hailstones of a Spherical Form, . . . 85 



XL Account of an attempt to ascend Chimborazo, made 

 on the 16th December 1831. By J. B. Boussin- 

 gatjlt. In a letter addressed to Alexander Von 

 Humboldt, ..... 88 



XII. On the Characters of certain groups of the Class 



Personatee. By David Don, Esq. Libr. L. S., &c. 108 



XIII. Account of the Discovery by Purkinje and Valentin 

 of Ciliary Motions in Reptiles and Warm-blooded 

 Animals ; with Remarks, and additional Experi- 

 ments. By William Sharpey, M.D., F.R.S.E., 

 Lecturer on Anatomy, . . . 114 



Discovery of Continual Vibratory Motions produced 

 by Cilia, as a general Phenomenon in Reptiles, 

 Birds, and Mammiferous Animals. By Professor 

 Purkinje and Dr Valentin, of Breslaw, . 118 

 Parts of the Body, rnd Classes of Animals, in which the 



Vibratory Motions exist, . . -. . 119 



Method of Investigation, . . . '. 121 



Nature and Character of the Vibratory Motions, . 122 

 Additional Observations and Experiments, by Dr 

 Sharpey, . . . . .125 



