Dr. Hamilton on a Plant allied to the Genus Piper. 9 



mobility when the eyeball is displaced by an external force. 

 If this result (which I state with much diffidence, from hav- 

 ing only my own experience in its favour) shall be found ge- 

 nerally true by others, it will follow that the objects of men- 

 tal contemplation may be seen as distinctly as external ob- 

 jects, and will occupy the same local position in the axis of 

 vision, as if they had been formed by the agency of light.* 



Hence all the phenomena of apparitions may depend upon 

 the relative intensities of these two classes of impressions, and 

 upon their manner of accidental combination. In perfect 

 health, when the mind possesses a control over its powers, 

 the impressions of external objects alone occupy the attention, 

 but in the unhealthy condition of the mind, the impressions 

 of its own creation either overpower, or combine themselves 

 with the impressions of external objects ; — the mental spectra 

 in the one case appearing alone, while in the other they are 

 seen projected among those external objects to which the eye- 

 ball is directed. 



Art. II. — An Account of a Plant allied to the Genus Piper. 

 By Francis Hamilton, M. D. F. R. S. F. A. S. Lond. 

 and Ed. Communicated by the Author. 



The different species of the genus Piper, as constituted by 

 Linnaeus from the Piper of the ancients, and the Saururus 

 of Plumier, offer a considerable number of differences in the 

 parts of the fructification, and attempts have been therefore 

 made to divide it into several genera. Swartz separated the 

 Lacistema, called Ncematosperrnum by Richard ; and this ar- 

 rangement seems to have met with general approbation. Ruiz 

 again restored the Saururus of Plumier under the new-fan- 

 gled name Peperomia, which has been adopted by several 

 excellent botanists, especially Kunth ; while others of equal 

 authority (Poiret and Vahl) object to this innovation (Enc. 

 Meth. Sup. iv. 454.) In fact, the separation would at any 

 rate appear to be premature ; for in the greater number of 

 species, the details of the fructification are still wanting, and 



• These results, and several others which I shall have occasion to explain 

 in another paper, confirm, in a remarkable manner, the views of my friend Dr. 

 Jlibbert, in his able work on the Philosophy of Apparitions. 



