Miscellaneous. 457 



violently fractured : the same thing is observed in other mine- 

 ral substances while undergoing particular chemical or molecular 

 changes. 



Of the phenomena described by the author as examples of phos- 

 phorescence in flowering plants, most, if not all, must be regarded as 

 originating in electrical action ; but the luminosity of certain Fungi 

 rests upon a good foundation. The catalogue of luminous animals 

 is a long one, and the chief points connected with them are well 

 discussed by Dr. Phipson, in whose pages the reader will find an 

 interesting account of a great number of curious phenomena. 



In his theoretical view of the nature of phosphorescence, the author 

 endeavours to bring all these multifarious phenomena under the same 

 category ; and here, we think, he is scarcely successful. At the base 

 of his theory lies the correlation of the physical forces and their 

 mutual convertibility ; such a conversion of forces into light he 

 assumes to take place in phosphorescent bodies, and thus thinks he 

 has accounted for their phosphorescence. Thus the insolation of 

 Bologna phosphorus, according to him, sets up certain vibrations 

 (electric, chemical, or magnetic) in that body, which cease on its 

 being removed into the dark, and, in ceasing, cause the emission of 

 a proportionate amount of light. In hke manner, on the application 

 of heat to a body which emits light at a comparatively low tempera- 

 ture, we should have a certain amount of heat converted into light 

 when a given point is reached. In these cases, such an hypothesis 

 may certainly be the true one, but it is still far from explaining the 

 phenomena ; for a theory of phosphorescence ought at least to show 

 some plausible reason why light is emitted under certain conditions 

 by one body and not by others. 



The luminosity of the Fungi is regarded by Dr. Phipson as due to 

 chemical action ; but, curiously enough, that of animals is ascribed 

 to the conversion of nerve-force into light, although the luminous 

 matter even of the higher forms of phosphoric animals (insects and 

 Myriapods) will continue shining when smeared over other objects. 

 Under these circumstances, and considering that decayed wood and 

 putrescent animal matter are often luminous in the dark, we should 

 prefer regarding the phosphorescence both of animals and plants as 

 due to a chemical action, the subjection of which to the will in the 

 former does not seem to present any special difficulty. 



MISCELLANEOUS. 



Notice of three Womhats in the Zoological Gardens. 

 By Dr. J. E. Gray, F.R.S. &c. 

 There are at present in the Zoological Gardens in the Regent's 

 Park three kinds of Wombats from Australia : two were sent from 

 the Acclimatization Society of South Australia, at Victoria ; but no- 

 thing is known of their peculiar habitat. They are evidently dis- 

 tinct from the common silver-grey Wombat, which we have long 

 had alive. 



Ann. ^ Mag. N. Hist. Ser. 3. Vol. xi. 30 



