4.72 



lonyx^ and Pcdmurus qiiadricornis are next described, and an ex- 

 planation attempted of the uses of the several parts and their sub- 

 serviencj" to the purposes of that sense. 



The author concludes by a description of another organ situated 

 at the base of the large antennae, which it appears has been con- 

 founded with the former by some anatomists, but vrhich the author 

 conjectures may possibly constitute an organ of smell. The paper 

 is accompanied by illustrative drawings. 



5. " A statement of Experiments showing that Carbon and Ni- 

 trogen are compound bodies, and are made by Plants during their 

 growth." By Robert Rigg, Esq., F.R.S. 



The author, finding that sprigs of succulent plants, such as mint, 

 placed in a bottle containing perfectly pure water, and having no 

 communication with the atmosphere except through the medium of 

 water, or mercury and water, in a few weeks grow to more than 

 double their size, with a proportionate increase of weight of all the 

 chemical elements which enter into their composition, is thence 

 disposed to infer that all plants make carbon and nitrogen ; and that 

 the quantity made by any plant varies with the circumstances in 

 which it is placed. 



6. " Physiological inferences derived from Human and Compara- 

 tive Anatomy respecting the Origins of the Nerves, the Cerebellum, 

 and the Striated Bodies." By Joseph Swan, Esq. Communicated 

 by Richard Omxu, Esq., F.R.S. 



The author remarks that those parts of the nervous system which 

 are concerned in motion and in sensation exliibit a great similarity 

 in all vertebrate animals. To the first of these functions belong the 

 anterior and middle portions of the spinal cord and medulla oblon- 

 gata, including the anterior pyramids, the crura cerebri, and some 

 fibres leading to the corpora striata and the convolutions, and also 

 the cerebellum. To the function of sensation belong the posterior 

 surface of the spinal cord, the posterior and lateral portions of the 

 medulla oblongata, including the posterior pyramids, the ventricular 

 cords, and the fourth and third ventricles. 



From a general comparison of the relative magnitude and struc- 

 ture of these several parts in the different classes of vertebrated 

 animals, the author infers that only a very small portion of the brain 

 is necessary for the origins of the nerves, their respective faculties 

 being generally derived near the place at which they leave the brain. 

 These origins are traced in various cases, where, from peculiarities 

 of arrangement or of destination, they present certain remarkable 

 diff'erences of situation. 



The author is led to consider the cerebellum as an appendage 

 to the brain, rather than to the medulla oblongata and spinal 

 nerves, for it does not correspond with either the number or the 

 size of the -sensitive or motor nerves ; and that it is not required 

 for the intellect, for the special senses, for common sensation, or for 

 'volition, appears from its size bearing no proportion to the strength of 



