394 FREAKS OF PLANT LIFE. 



very rough and black. The interior tissue, at first 

 whitish, afterwards of a more or less deep brown 

 colour, is formed of long parallel filaments. The 

 phenomena of luminosity in these fungi have been 

 made the subject of investigation by M. Tulasne. 

 " On the evening of the day when I received the 

 specimens," he writes, " the temperature being about 

 22° C, all the young branches brightened with an 

 uniform phosphoric light the whole of their length ; 

 it was the same with the surface of some of the 

 older branches, the greater number of which were 

 still brilliant in some parts, and only on their surface. 

 I split and lacerated many of these twigs, but their 

 internal substance remained dull. The next evening, 

 on the contrary, this substance having been exposed 

 to contact with the air, exhibited at its surface the 

 same brightness as the bark of the branches. Pro- 

 longed friction of the luminous surfaces reduced the 

 brightness and dried them to a certain degree, but 

 did not leave on the fingers any phosphorescent 

 matter."! And again : " By preserving these Rhizo- 

 morphae in an adequate state of humidity, I have 

 been able for many evenings to renew the examina- 

 tion of their phosphorescence ; the commencement 

 of dcssication, long before they really perish, deprives 



1 " Tulasne sur la Phosphorescence," " Ann. des Sci. Nat." 

 (1848), vol. ix., p. 340, &c. 



